Logic Riddles And Answer | Best Riddles and Brain Teasers

#471 - Liar and truth teller riddle

Katniss and Peeta are liars. They both lie on some specific days.

Katniss lies of Fridays, Saturdays and Sundays. She speaks truth on all other days.

Peeta lies on Tuesdays, Wednesdays and Thursdays. He speaks truth on all other days.

Can you tell that one day of the week when both of them will say "Tomorrow, I will lie."?

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Thursday.

Suppose that the person is speaking truth, he/she will have to lie on the next day but if he/she speaks lie by saying "Tomorrow I will lie.", then he/she will have to speak truth on the next day.

Thus, in each of the case, they will have to change their behavior the next day.

Now if you analyze, you will find out that Katniss can only say that statement on Thursday or Sunday. Peeta can say that statement on Monday or Thursday. Thus the only day common is Thursday.

#472 - Challenging Logic Problem

You order chicken wings at KFC in the boxes of 6, 9 and 20. What is the largest number of wings that you cannot obtain by buying in any combination of the boxes?

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43

You know that you can purchase any number of wings that is divisible by 3 but of course it should not be 3 itself. Thus, you should just try to purchase using the combinations of 9 and 6 boxes till the number is divisible by 3. If that number is not divisible by 3, then you have to use a box with 20. If the number that remains is divisible by 3, you are game. But if it is not divisible by 3, you can use a second box of 20. The number now will necessarily be divisible by 3.

Thus the largest number of wings that cannot be bought will come after buying two boxes of 20 and leaving a remainder that is divisible by 3:
3 + 20 + 20 = 43.

#473 - Who Is Speaking The Truth Puzzle

Before reading ahead, you must know the fact that only one of the person here is telling the truth.

A says that B is lying.
B says that C is lying.
C says both A and B are lying.

Can you find out who is speaking the truth?

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B is speaking the truth.

A is lying when he says that B is lying. B is telling the truth when he says that C is lying. C is lying when he says that both A and B are lying since one of them is speaking the truth.

#474 - Logic Puzzle Question

You are camping with your friends. You have a flashlight for any emergency and have brought 8 batteries along with you. Your brother calls to tell you that four of those batteries are already dead.

Your flashlight requires two working batteries to run. What is the least number of pairs you will need to test to guarantee that you can get the flashlight on ?

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7
You must first divide the batteries in three groups: a group of two batteries and two groups of three batteries each. Now you have made sure that one of the group has two working batteries.

Now both the groups with three batteries can form three possible combinations and the group with two batteries has just one combination.

3 + 3 + 1 = 7.

#475 - Trick Matchstick Problem

Can you find out a way through which you can make five squares out of the given figure by moving just six match sticks?

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Many of you might have tried making five different squares but that was not asked in the question. See the figure for the explanation.

#476 - Counting Apples Basket Problem

In a basket of apples,
when counted in twos, there was one extra
when counted in threes, there were two extra when counted in fours, there were three extra
when counted in fives, there were four extra
when counted in sixes, there were five extra.

However, if the apples were counted in sevens, no extra apple was left. Can you calculate the minimum number of apples that were present in the basket ?

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119

Let the number of apples = X
X / 2 => Remainder = 1
X / 3 => Remainder = 2
X / 4 => Remainder = 3
X / 5 => Remainder = 4
X / 6 => Remainder = 5
X / 7 => Remainder = 0

Therefore, X is divisible by 7.

Whenever X is divided by any number less than 7, the remainder is 1 less than the divisor.
=> X + 1 is the LCM of 2, 3, 4, 5 and 6.

Now LCM of 2, 3, 4, 5 and 6 = 60
But 60 - 1 = 59 is not divisible by 7

60 * 2 = 120
120 - 1 = 119 which is divisible by 7

This means that X + 1 = 120 or X = 119

Number of minimum number of apples in the basket = 119

#477 - Lateral Thinking Game Winner Puzzle

Aaron, Brad, Christopher, Danny and Elvis decided to play a game of tiddly winks. In this game they decided that one win will get 1 point for winning, 0 for losing and 1/2 in case of a tie.

They finished the game in alphabetical order and it was found that the scores were different for each person.

Based on the following two statements, can you find out the result of the individual games?
Brad: No one could finish like me, without a loss.
Elvis: No one played worse than me, I finished without a single win.

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One of the possible solution is given below:
Aaron lost to Brad, but won every other game for a total of 3 points.
Brad beat Aaron, but tied in all other games for a total of 2.5 points.
Christopher beat Danny and tied with Brad and Elvis for 2 points.
Danny beat Elvis and tied only with Brad for 1.5 points.
Elvis tied with Brad and Christopher for 1 point.

#478 - Confusing Lost Chocolates Puzzle

Alex bought 150 chocolates but he misplaced some of them. His mother asked him how many chocolates were misplaced and he gave the following answer to her:
If you count in pairs, one remain
If you count in threes, two remain
If you count in fours, three remain
If you count in fives, four remain
If you count in sixes, five remain
If you count in sevens, no chocolate remain.

Can you analyze the statements and tell us how many chocolates were lost?

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119 chocolates were lost.

#479 - Classic Two Bottles Pill Puzzle

You have two bottles of pills marked with the label A and B. The pills are identical. The doctor has asked you to take one A pill and one B pill daily. You cant take more or less than that.

While taking out the pills one day, you took out one pill from A and by mistake took out two from B. You have no idea which pill is which now.

You cant throw away the expensive pills. What will you do now?

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Cut each of the three pills in half and put each half in two piles. Now, each of the two piles will contain half of pill A and two halves of pill B.

Take one pill A and cut into half and put the two halves in the two piles. Now, each pile will have two halves of pill A and two halves of pill B which means one pill A and one pill B. You can take one pile today and one pile the next day.

#480 - Short Story Birbal Riddle

A man was convicted of a minor offense in Akbar court. Akbar decided to give him a chance. He asked him to give a statement. If the statement is true, he will be killed by lions and if it is false, he will be killed by trampling of wild elephants.

The convicted person requested help from Birbal and since the crime was not a big one, Birbal decided to help him. Whatever Birbal suggested impressed Kabir and he let the convicted person go.

What did Birbal suggest to the person?

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The statement was "I will be killed by trampling of wild elephants."

Now if the statement is true, he should be killed by lions but then the statement will become false.
If the statement is false, he will be killed by trampling elephants, which will make the statement true.