10 Logic Games To Test How Smart You Really Are

You’re the type to look beyond the obvious, uncover underlying patterns, and arrive at great solutions. Solve these puzzles, and you just might be right for the challenge of a career at EY.

1. Reading Labels

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There are three boxes in front of you. One is labeled "APPLES," another is labeled "ORANGES,” and the last one is labeled "APPLES AND ORANGES.” You know that each is labeled incorrectly. You may ask me to pick one fruit from one box which you choose.

How can you label the boxes correctly?

Solution:

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This box must contain either only apples or only oranges.

E.g. if you find an orange, label the box orange, then change the oranges box to apples, and the apples box to "APPLES AND ORANGES."

2. The Football Family

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Bill, Ken, and Mark are — not necessarily in this order — a quarterback, a receiver, and a kicker. The kicker, who is the shortest of the three, is a bachelor. Bill, who is Ken's father-in-law, is taller than the receiver.

Who plays in which position?

Solution:

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Since Bill is Ken's father-in-law, both Bill and Ken must be married. This leaves the only remaining person, Mark, to be the bachelor (and hence the kicker). Since Bill is taller than the receiver, Bill must not be the receiver. By process of elimination, we conclude that Bill is the quarterback. The remaining position (the receiver) goes to Ken.

3. The Trustworthy Troll

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You’re trapped in a room with two doors. One leads to certain death, and the other leads to freedom. You don't know which is which.

There are two trolls guarding the doors. They will let you choose one door, but upon doing so, you must go through it.

You can, however, ask one troll one question. The problem is one troll always tells the truth, and the other always lies — and you don't know which is which.

What is the question you ask?

Solution:

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Then go through the other door.

4. The Frog and the Well

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A frog is at the bottom of a 30-meter well. Each day he gathers enough energy for one three-meter leap up the well. Exhausted, he then hangs there for the rest of the day. At night, while he sleeps, he slips two meters backwards. How many days does it take him to escape from the well?

Note: Assume after the first leap that his hind legs are exactly three meters up the well. His hind legs must clear the well for him to escape.

Solution:

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Each day he makes it up another meter, and then on the 27th day he can leap three meters and climb out.

5. The Paddler

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It’s a beautiful day, and you’re out for a canoe ride. You know that you can paddle your canoe seven miles per hour and that the stream flows at three miles per hour.

The moment you start to paddle upstream, a fisherman loses one of his bobbers in the water 14 miles upstream of you.

How many hours does it take for you and the bobber to meet?

Solution:

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Ignore the speed of the stream as the bobber will be carried along at three miles per hour, as will you. It takes two hours to travel 14 miles at a rate of seven miles per hour.

6. Sock It to Ya

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You’re in a hurry and realize you forgot your socks! You race back to your room, but all the lights are off, so you can't see the color of the socks.

Luckily, you remember that in your drawer there are 10 pairs of white socks, 10 pairs of black socks, and 11 pairs of blue socks — but they’re all mixed up.

How many of your socks do you need to take before you can be sure to have at least one matching pair?

Solution:

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Although there are many socks in the drawer, there are only three colors, so if you take four socks then you are guaranteed to have at least one matching pair.

7. Truths and Lies

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A. The number of false statements here is one.

B. The number of false statements here is two.

C. The number of false statements here is three.

D. The number of false statements here is four.

Which of the above statements is true?

Solution:

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Three statements are false. Since each statement concludes that there is a different number of false statements, that proves that only one statement can be correct (hence the object is to decide which statement is true). Given that one statement is true, by definition, the other three must be false!

8. Out of Your Marbles

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Given 12 marbles that are identical in size, shape, and color, determine which single marble is heavier in weight than the others. You are supplied with a balance and must conclude your determination in three weighings.

Solution:

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First, weigh all 12 marbles, six on each side of the scale (weighing number one). Whichever side is heavier, take those six marbles and weigh three on each side (weighing number two).

Again, whichever side is heavier, take those three marbles, placing one to the side and weighing the other two, one on each side of the scale (weighing number three).

During this weighing, if one marble weighs more than the other, the answer is obvious, and so too, if they balance perfectly, then the marble you put to the side is the heavier marble!

9. Have Your Cake

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How is it possible to cut a traditional, circular cake into eight equal size pieces with only three cuts?

Solution:

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10. A Real Puzzle

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If the puzzle you solved before you solved the puzzle you solved after you solved the puzzle you solved before you solved this one was harder than the puzzle you solved after you solved the puzzle you solved before you solved this one, was the puzzle you solved before you solved this one harder than this one?

Solution:

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There are only two puzzles being spoken of: this one, and the one before this one. The entire question could be rephrased like this:

If the puzzle you solved before this one was harder than this one, was the puzzle you solved before this one harder than this one?

Obviously, the answer to the question is simply yes.