Professor Layton and the Curious Village/Puzzles 26-50

Puzzle 026

 * Name: Bottle Full of Germs
 * Trigger: Tap on the Jar
 * Location: Park Gate
 * Chapter: 2
 * Picarats: 20

Description: A glass jar holds a single germ. After one minute, the germ splits into two germs. One minute after that, the two germs each split again, forming a total of four germs. Continuing at this rate, a single germ can multiply to fill the whole jar in exactly one hour. Knowing this, how long in minutes would it take to fill the jar if you had started with two germs?


 * Hint 1: If one germ becomes two, and two become four, that means that the number of germs doubles each minute.
 * Hint 2: If you start with one germ, the germ will multiply and fill the jar in one hour. Starting with one germ, then, how many will you have in one minute? Read the problem carefully.
 * Hint 3: Let's take a step back and think. Your answer is the amount of time it takes for two germs to fill the jar. If it takes one minute for one germ to turn into two, how much additional time is needed to fill the jar?

Answer: 59

Puzzle 027

 * Name: Bickering Brothers
 * Trigger: Talk to Gordon
 * Location: Manor Parlor
 * Chapter: Between 2 and 3
 * Picarats: 30

Description: Six brothers have gathered around a table to eat dinner. Each or the brothers is prone to fighting with the siblings directly above and below him in age and can't be seated next to either of them. Also, Brothers 3 and 5 got into an argument the other day and refuse to sit next to each other. The eldest brother (Brother 1) has already sat down at the big table and is waiting on the others to start eating. Can you find a seating arrangement that will keep everyone from fighting with each other?


 * Hint 1: Don't spend too much time trying to think it out. Instead, just move those brothers around and see what develops. There are only three seats Brother 2 can sit in because he can't sit next to Brother 1. Plop him down in any one of those seats and move on to Brother 3. We know Brother 3 can't sit next to Brother 2...and so on and so forth.
 * Hint 2: This puzzle would be a breeze if it weren't for the spat between Brother 3 and Brother 5. What a pain they are. Sit Brother 3 next to Brother 1. That ought to keep the little guy in line.
 * Hint 3: You already know to sit Brother 3 next to Brother 1. Next, sit Brother 4 directly across the table from Brother 1. The rest is up to you.

Answer: Going clockwise: 1-3-6-4-2-5 or 1-5-2-4-6-3

Puzzle 028

 * Name: Find the Dot
 * Trigger: Talk to Matthew
 * Location: Manor Parlor
 * Chapter: Between 2 and 3
 * Picarats: 30

Description: You are holding an eight-pointed shape with a red dot on it. If you hold the shape so that the red dot is in the position shown in Diagram A, then flip it over, you'll see a black dot as depicted below. Now, assume you are holding the shape as shown on the left side of Diagram B. Where will the black dot be when you flip the shape over? Draw a circle around where you think the black dot should go.


 * Hint 1: If you flip the shape in Diagram A, you get the shape shown in the upper-right part of the screen. Try to visualize where that black dot is when the white side is up. Diagram B is just a rotated version of Diagram A, so you know that the position of the black dot in Diagram B must also rotate accordingly.
 * Hint 2: When the shape is positioned as shown in A, the black dot is behind the middle-right prong of the shape. Flip the shape over and you'll see it on the middle-left prong. See how the dot moves when you flip the shape over? Now think about where that dot should be in the orientation showed in B.
 * Hint 3: Moving clockwise, when the white side is facing up (as in the left picture of B), the black dot is two spaces ahead of the red dot. Now you should pretty much know where the black dot is. Just visualize the shape flipping over and you'll have your answer.

Answer: Put your stylus on the topmost point. Going clockwise, move down  three points. This is the answer. The black dot is in the same place as the red dot in diagram B. Looking at it another way, if the shape was a compass rose, the answer is in the South East position. Circle the dot and hit SUBMIT.

Puzzle 029

 * Name: Five Suspects
 * Trigger: Talk to Inspector Chelmey
 * Location: Manor Parlor
 * Chapter: 3
 * Picarats: 20

Description: Five suspects are called into police headquarters for questioning. They give the following statements. A:"One of the five of us is lying." B:"Two of the fuve of us are lying." C:"I know these guys, and three of the five of us are lying." D:"Don't listen to a word they say. Out of the five of us, four are lying." E:"All five of us are dirty rotten liars!" The police only want to release the suspects who are telling the truth. How many people should they let go?


 * Hint 1: This puzzle might look like a big mess at first, but it's fairly simple when all is said and done. Take E, for example, who says everyone is lying. If she is actually telling the truth, then her statement becomes a lie, and she must be ruled out. Yep, E's a liar for sure.
 * Hint 2: Let's rule out another couple of suspects. If A's statement is true, then three other people should be saying the same thing as A. This is not the case, so A is a liar. If B is telling the truth, two other suspects should say the same thing as B. Once again, this is not the case, so B must be lying.
 * Hint 3: So, to sum things up, so far we've proven that A, B, and E are lying. Let's examine the last two suspects. If three people are lying, the other two suspects should have the same statement, but everyone is saying something different. On the other hand, if four of the five suspects are lying...

Answer: 1

Puzzle 030

 * Name: One-Line Puzzle 1
 * Trigger: Talk to Agnes
 * Location: Manor Border
 * Chapter: 3
 * Picarats: 30

Description: Have you heard of one-line puzzles? The idea is to place your pen to paper and draw a shape without lifting your pen from the pad or retracing any part of the line. You can, however, cross lines. Now that you're familiar with the concept, look at the four pictures below. One of them cannot be drawn with one line. Which one is it?


 * Hint 1: Each picture should be composed of lines that meet at different points. With these pictures, if you find a single line that runs out beyond the others, you know you have to start your drawing there. Try tracing the answer out yourself.
 * Hint 2: Some points may be the convergence point for several lines. You need to think hard about which line to take in and out of the point in order to make the sketches work. If your pen is entering a point formed by an even number of lines, you will always be able to leave the point via another line.
 * Hint 3: One of the familiar objects below can't be drawn as a one-line puzzle. You'd be surprised by how easily some of the more complicated pictures can be drawn in one stroke.

Answer: Circle the picture in the lower-left corner (the one that looks like a house). Hit SUBMIT.

Puzzle 031

 * Name: Racetrack Riddle
 * Trigger: Talk to Marco
 * Location: Manor Road
 * Chapter: 3
 * Picarats: 30

Description: The distance three racehorses can run around the racetrack in one minute is listed below. Horse A: Two laps. Horse B: Three laps. Horse C: Four laps. The horses line up at the starting line and start running in the same direction. How many minutes will pass before all three horses line up at the starting line again?


 * Hint 1: Someone in a hurry might just to the conclusion that you need to find the lowest common multiple between the three numbers. Read the problem over again and see if you can' clear things up for yourself.
 * Hint 2: The three horses each run at different speeds. To measure the horses' speeds, the problem tells you how many laps each horse can do in one minute. The horses all run whole laps per minute, so at least you don't have to deal with strange speeds.
 * Hint 3: One horse runs two laps in one minute, one runs three laps in one minute, and one runs four laps in one minute. Where will the horses be one minute after they start running?

Answer: 1

Puzzle 032

 * Name: Candy Jars
 * Trigger: Tap the Candy Jars on the Counter (Layton's puzzle)
 * Location: General Store
 * Chapter: 3
 * Picarats: 30

Description: You have 10 jars filled with 50 pieces of candy each. You then pour the candy into small bags and attempt to get half a jar in each bag. Now you have 20 bags of candy. What is the percentage likelihood that there are an average of 25 pieces of candy in a single sack?


 * Hint 1: Each of the 10 jars holds 50 pieces of candy, for a total of 500 pieces. You've taken this mountain of candy and divided it into 20 bags. Pretty straightforward so far, right? If you've made it this far, try reading the puzzle again carefully.
 * Hint 2: Think carefully. What exactly is the puzzle asking you? That's right, you need to figure out the percentage likelihood that there will be an average of 25 pieces of candy per bag. That's different from simply asking the percentage likelihood that a bag contains 25 pieces of candy, isn't it?
 * Hint 3: This will pretty much give the answer away, but since you paid for a hint, let's break it down, shall we? Ten jars with 50 pieces to a jar means you have 500 pieces of candy in total. If you divide those 500 pieces into 20 bags, you get 25 pieces...Now think about what exactly that number signifies.

Answer: 100

Puzzle 033

 * Name: Light Which One?
 * Trigger: Tap the Candle (Layton's Puzzle)
 * Location: General Store
 * Chapter: 3
 * Picarats: 20

Description: You have only one match left. You want to light the room with an oil lamp, start a fire to warm the room, and heat your bathwater. In order to complete all of the above actions, which of these should you light first?


 * Hint 1: Does the order in which you light the items matter? Of course it does! Think about the item you have to light first.
 * Hint 2: Your answer should be the item that, once lit, lets you perform your other tasks. Without lighting this, you won't be able to take care of anything else.
 * Hint 3: This puzzle is devious in its simplicity. Just think about the situation logically and you'll have your answer.

Answer: Circle the match held by the man. Hit SUBMIT.

Puzzle 034

 * Name: How Many Sheets?
 * Trigger: Talk to Percy
 * Location: Plaza
 * Chapter: 3
 * Picarats: 40

Description: Several rectangular sheets of transparent film are arranged on top of each other as shown. This lines represent areas where one sheet overlaps with another. At the thickest point of this pile, how many sheets are overlapping?


 * Hint 1: Three layers here, four layers there... Label each overlap you discover.
 * Hint 2: Only one area of the image contains the maximum number of overlaps.
 * Hint 3: There are a total of seven sheets of film in this picture. The solution for this problem is a number smaller than seven.

Answer: 5

Puzzle 035

 * Name: Strange Dots
 * Trigger: Talk to Deke
 * Location: Plaza
 * Chapter: 3
 * Picarats: 20

Description: The dice below look normal enough, but if you look carefully, you should see a pattern start to emerge. You know the following: A=0, B=9, C=6. So what does D correspond to?


 * Hint 1: Look at the different dice shown. Now look up from your game and think for a moment. Can you think of anything in your environment that shares a strong connection to numbers? It's something just about everyone sees on a daily basis.
 * Hint 2: The first hint states that the dice share a connection with an item in your environment that most people see on a daily bases. However, this item has come to take a completely different shape recently. The newer version of this mystery item shares no connection with this puzzle.
 * Hint 3: The dice represent an object you are very familiar with. In fact, you probably have one hanging in on your wall or strapped to your wrist right now!

Answer: 3. The dots on the dice represent number positions on an analog clock.

Puzzle 036

 * Name: Too Many Mice
 * Trigger: Tap on the Alley Cat (Layton's Puzzle)
 * Location: Clock Tower
 * Chapter: 3
 * Picarats: 30

Description: Mice are famous for their ability to multiply at breakneck speeds. The type of mouse we have here gives birth once a month, birthing 12 babies each time. Baby mice mature and can give birth two months after they are born. You picked up one of these darling baby mice at the pet shop and brought it home the day after it was born. In 10 months from now, how many mice will you have?


 * Hint 1: You may be thinking there's going to be a lot of bothersome calculation involved in solving this puzzle, but you don't need to do anything complicated to find the answer. Read the problem over carefully.
 * Hint 2: Do you remember how many mice you started with? Have you considered how many mice you can expect, given that number?
 * Hint 3: Ok, let me spell it out for you. You need your mouse to become pregnant before it will give birth. What does the mouse need in order to become pregnant?

Answer: 1

Puzzle 037

 * Name: Brother and Sister
 * Trigger: Talk to Lucy
 * Location: Clock Tower
 * Chapter: 3
 * Picarats: 40

Description: A boy and his big sister are sitting around the kitchen table chatting. "You know Sis, if I took away two years from my age and gave them to you, you'd be twice my age, huh!" "Well, why don't you just give me one more on top of that? Then I'll be three times your age." So just how old is each  sibling?


 * Hint 1: Let's see if we can't pare this puzzle down a bit. When you take two years away from the brother's age and add them to the big sister's, she becomes twice his age. Additionally, when you take three years away from the brother and give them to the sister, she becomes three times older than he is.
 * Hint 2: You could try and solve this with an algebraic equation, but that's no way to tackle a puzzle! Try to reason your way through this one. Move two years from the brother's age, and the difference in age becomes four years. Move three years, and the difference widens to six years. Four years makes the sister twice as old as the boy. Six years makes her three times as old.
 * Hint 3: The brother and sister were born in the same year.

Answer: The brother and sister are both 6.

Puzzle 038

 * Name: Island Hopping
 * Trigger: Talk to Zappone
 * Location: Fork in the Road
 * Chapter: 3
 * Picarats: 20

Description: Here is an overhead view of a cluster of tropical islands. As you travel from Start to Goal, your objective is to visit every island exactly one time. The island folk say this can be accomplished with the addition of a single straight bridge. The only other rule is that your bridge can't cross over any preexisting bridge. So, where should your bridge go?


 * Hint 1: You need to visit each island exactly one time, but that doesn't mean that you have to cross every bridge to do so.
 * Hint 2: Try setting out from the start point and just proceeding on your merry way. If you come across an island you simply can't get to, you may have just stumbled upon your answer.
 * Hint 3: Examine the are around the middle of the island cluster closely.

Answer: Draw a bridge from the middle island containing a house with a purple roof to the island with the gray lighthouse on the left part of the screen. Hit SUBMIT.

Puzzle 039

 * Name: One-Line Puzzle 2
 * Trigger: Talk to Agnes
 * Location: Fork in the Road
 * Chapter: 3
 * Picarats: 30

Description: The idea of one-line puzzles is to put your pen to paper and draw a shape without lifting your pen from the pad or retracing any lines. You can, however, cross lines. Now that you're familiar with the concept, look at the four pictures below. One of them cannot be drawn with one line. Which one is it?


 * Hint 1: Each picture should be composed of lines that meet at different points. With these pictures, if you find a single line that runs out beyond the others, you know you have to start your drawing there. Try tracing the answer out yourself.
 * Hint 2: Some points may be the convergence point for several lines. You need to think hard about which line to take in and out of the point in order to make the sketches work. If you pen is entering a point formed by an even number of lines, you will always be able to leave the point via another line.
 * Hint 3: Using Hints One and Two, it's actually quite easy to draw these shapes out yourself. Make sure that you start drawing the shape form a point that touches an odd number of lines. Don't forget, one is also an odd number.

Answer: Circle the picture of the top hat in the upper right. Hit SUBMIT.

Puzzle 040

 * Name: How Old Is Dad?
 * Trigger: Talk to Archibald
 * Location: Market
 * Chapter: 3
 * Picarats: 30

Description: A father and son are chatting when the son poses this question: "Dad, I'm 22 now, but just how old are you?" The father replies, "You wanna know how old your old man is, eh? Hmm, well, I tell you what. I'm as old as your age, plus half of my age." How old is the father?


 * Hint 1: It sounds convoluted, but look again at what's being presented. "I'm as old as your age, plus half of my age." This means that if you take away half of the father's age, you'll have the age of the son. As you already know, the son is 22.
 * Hint 2: What the father is essentially saying here is that if you add half of his age to the son's age, you'll get the father's age. If that's the case, the son's age must be half of the father's age.
 * Hint 3: As started in the second hint, half of the father's age is equal to the son's age. To put it another way, the father's age is two times that of his son.

Answer: 44

Puzzle 041

 * Name: Spare Change
 * Trigger: Talk to Gerard
 * Location: Northern Path
 * Chapter: 3
 * Picarats: 10

Description: A rope and coins are arranged as shown below. As you pull the ends of the rope out to the left and right, the rope will draw taut and push the coins to either side. Assuming you only get to keep the coins that end up on the top half of the rope, how many coins will you have?


 * Hint 1: There's no special trick to this puzzle. You just need to be diligent and count up those coins.
 * Hint 2: Try tracing the rope with your stylus as you count up the coins. If you fill in the area that will travel upward when the rope is taut, you should be able to get an answer without too much work.
 * Hint 3: There are 32 coins tangled in the rope. When all is said and done, you don't even pull in a third of them.

Answer: 9

Puzzle 042

 * Name: The Camera and Case
 * Trigger: Talk to Gerard
 * Location: Northern Path
 * Chapter: 3
 * Picarats: 50

Description: While walking through a market on vacation, you notice a small stand selling cameras. A camera-and-case set is selling for $310. The seller tells you that the camera costs $300 more than the case itself and that the case costs the price of the set minus the cost of the camera. You decide you'd rather wait on buying a camera and opt to just buy the case alone. You hand the seller a $100 bill and see his eyes light up. Think fast now! How much change should you be getting back?


 * Hint 1: This puzzle isn't math intensive, but there is a particularly tricky aspect to it that trips most people up. The camera and case cost a total of $310 but differ in price by $300.
 * Hint 2: Ok, if you assume the case costs X, then the camera must cost X plus $300. This means that the camera itself must cost more than $300.
 * Hint 3: The case and camera cost $310 together. The camera costs $300 more than the case. It may seem like the answer is $300 for the camera and $10 for the case, but if you do the math, you'll see that the difference in price is only $290. Have you noticed that already?

Answer: 95

Puzzle 043

 * Name: Three Umbrellas
 * Trigger: Talk to Lucy
 * Location: Clock Tower
 * Chapter: 3
 * Picarats: 20

Description: Three identical-looking umbrellas are sitting upright in a stand. Assuming the owners don't check their umbrellas' labels, what percentage chance is there that only two people will walk off with their own umbrella?


 * Hint 1: Don't lose focus of what's being asked. Keep in mind that you aren't being asked the percentage likelihood of you grabbing your own umbrella form a group of three.
 * Hint 2: If two people have already successfully taken their own umbrellas, then who does the final umbrella belong to?
 * Hint 3: Three umbrellas sit in a bin. Two people come by and take their own umbrellas by chance, but the third person fails to do so... Hey, is that even possible?

Answer: 0 (Zero)

Puzzle 044

 * Name: Stamp Stumper
 * Trigger: Talk to Rodney
 * Location: Town Hall
 * Chapter: 3
 * Picarats: 50

Description: Your friend just got back from the post office where she purchased a sheet of stamps with values ranging from $.10 to $1.00. First, your friend cut out the $1.00 stamp and set it aside. Then she divided the remaining stamps into seven uniquely shaped bunches, each with a total value of $1.00. Can you divide this sheet of stamps the same way your friend did?


 * Hint 1: There's no trick to solving this one. You just need to try working things out dollar by dollar. You'll have an easier time of things if you start from the stamps with higher values, like $.80 or $.90. Just remember that each group of stamps must take a different shape.
 * Hint 2: Even if you've successfully divided the stamps into $1.00 groups, the answer won't count unless each group has a different shape. Here's one combination to get you started. The four stamps in the upper-left square of the sheet should be cut away to form a group.
 * Hint 3: The $.90 stamp in the sheet forms a group with the $.10 stamp to its right. Also, the three $.30 stamps form a group with the $.10 stamp located between them.

Answer: Start with the $.90 stamp. It forms a group with the $.10 stamp to its right. The $.70 stamp forms a group with the $.20 stamp above it and the $.10 stamp to its right. The $.80 stamp forms a group with the $.10 stamps above and below. The $.50 stamp forms a square group with the $.10 stamp in the upper-left corner and the $.20 stamps above and to the left of the $.50 stamp. The $.60 stamp forms a group with the $.10 stamp to its left, the $.20 stamp below it, and the $.10 stamp to the right of the $.20 stamp. The three $.30 stamps in the middle of the sheet form a group with the $.10 stamp in the middle. Lastly, the $.40 stamp forms a group with the $.20 stamp above, the $.10 stamp below, and the $.30 stamp in the bottom row.

Puzzle 045

 * Name: Puzzled Aliens
 * Trigger: Talk to Adrea
 * Location: Park Road
 * Chapter: 4
 * Picarats: 30

Description: From high in the sky, a pair of aliens observes humans using a bizarre object. Perplexed, one alien turns to the other and says: "How strange. The Earthling is opening a hole in a sheet of paper and marking it with a line to show the other Earthlings where the hole is. I've never seen anything like it!" What could these extraterrestrial visitors be talking about?


 * Hint 1: Even something as common as paper can look bizarre to someone who's never seen it before. What kind of device puts holes in paper? It must have a needle or sharp point on it.
 * Hint 2: This object uses a needle to punch a hole in a sheet of paper. Then it's used to draw a solid line around the hole. Since it draws a line, it must have some sort of writing implement attached to it.
 * Hint 3: It's safe to say that very few people ever use these once they grow up and join the working world. However, because of math class, a startling number of students probably have one in their bag or their desk at home.

Answer: Compass

Puzzle 046

 * Name: The Biggest Star
 * Trigger: Talk to Deke
 * Location: Park Gate
 * Chapter: 4
 * Picarats: 20

Description: Legend has it that people used to stare up at the heavens and find images of animals or important events in the constellations. Looking up at the star-filled sky here, try to connect the five largest objects in space to form the largest five-pointed star possible. Connect stars by drawing a line between them. Make sure that your line doesn't pass through another star along the way.


 * Hint 1: The shape you're trying to make is a five-pointed star. It's easy enough to form a star by just connecting five points, but you're aiming to make the biggest star possible. Look for "the five largest objects in space" and connect them together.
 * Hint 2: The answer for this puzzle requires you to draw your star upside down.
 * Hint 3: Remember that the planet we live on is also floating in space!

Answer: There are four noticeably larger stars in the sky. These make up four points of answer. The fifth point of the star will connect to the tree in the middle of the ground. To make the five pointed star, start and the tree and draw a line to the top-left large star. Now continue the line to the bottom-right large star. This star connects to the large star in the bottom-left, which then connects to the large star in the upper-right. Lastly, connect the star in the upper-right to the tree. Hit SUBMIT.

Puzzle 047

 * Name: On the Run
 * Trigger: Talk to Gerard
 * Location: Plaza
 * Chapter: 4
 * Picarats: 40

Description: A mysterious bandit is on the lam and trying to escape the police who are hot on his trail. His entrance into this part of town is marked with an arrow. This particular bandit follows a peculiar creed and hos vowed never to go backward or turn around. Additionally, whenever he meets an intersection, he will always turn left or right. Now, as you can see from the map, this part of town has multiple exits, which are labeled A through G. Of all the exits here, which one will the bandit never be able to pass through?


 * Hint 1: It's hard to get started on a puzzle that seems to present so many possibilities, but you'd be surprised at how much you can learn by simply trying out the various routes through town. The paths are littered with twists and turns, but if you try tracing any of the given paths, you can see how the bandit would make his way through town.
 * Hint 2: To simplify the question, what you're really looking for is an exit that's positioned so that the bandit has to turn away from it every time he draws near. Do you see any place like that on the map?
 * Hint 3: If you've tried any of the paths near the entrance the bandit came from, you know that the bandit can escape via A, G, F, and E. Your answer is one of the other three exits.

Answer: B

Puzzle 048

 * Name: Cats and Mice
 * Trigger: Tap the Ally Cat (Layton's Puzzle)
 * Location: Clock Tower
 * Chapter: 4
 * Picarats: 25

Description: Five cats can catch five mice in five minutes. With that in mind, how many cats does it take to catch 100 mice in 100 minutes?


 * Hint 1: Five cats can catch five mice in five minutes. If there were 10 mice running around, how long would it take for those same five cats to catch them?
 * Hint 2: Remember, this puzzle isn't asking how much time it takes to catch 100 mice. Read the problem again. The wording makes it easy to forget what you are really looking for.
 * Hint 3: Let's rethink this from the first step. Five cats can catch five mice in five minutes. So, in 10 minutes, they can catch 10 mice. In 20 minutes, they can catch 20 mice. How many cats are doing the catching?

Answer: 5

Puzzle 049

 * Name: 1,000 Times
 * Trigger: Talk to Lucy
 * Location: Clock Tower
 * Chapter: 4
 * Picarats: 20

Description: What on earth is this message getting at? The following is written on a piece of paper you pick up: "_ is 1,000 times _ _" To turn this strange message into a proper sentence, all you need to do is fill in the _ with a single letter of the alphabet. But what could it be? You'll need to use the same letter for all three _ s.


 * Hint 1: English only has 26 letters. If you try out each letter, you're bound to come across the solution eventually.
 * Hint 2: The puzzle talks about one object being 1,000 times another. Perhaps this phrase relates to size in some way?
 * Hint 3: This puzzle deals with units. Can you think of any letters used to indicate measurements of length?

Answer: M (one meter(m) is 1,000 x one millimeter(mm))

Puzzle 050

 * Name: OTTF?
 * Trigger: Talk to Marco
 * Location: Fork in the Road
 * Chapter: 4
 * Picarats: 20

Description: Here you have a set of small paper cards. On each card is a single letter, but one of the cards is missing its letter. What letter belongs on the blank card?


 * Hint 1: If you're guessing that there's some order to the way the cards are lined up, you're absolutely correct. Think about what series of things could be represented here.
 * Hint 2: How many cards do you have there? Ten, right? That's a bigger hint than you think. Look closely at which card is blank.
 * Hint 3: As odd as it may seem, all the knowledge you need to solve this puzzle you probably had from the day you stepped into first grade. It's safe to say that it's one of the first things you ever learned.

Answer: F (it's the first letter of "five")