#71 - Cross the river Athlete-Coach puzzle

There are three Athletes (Lavesh, Tarun and Harish) and their individual Coaches (Meher, Meenaxi and priyanka) standing on the shore.
No Coach trusts their Athlete to be near any other Coach unless they are also with them.
There is a boat that can hold a maximum of two persons.
How can the six people get across the river?

View Answer Discuss

Lavesh and Tarun cross, Lavesh returns
Lavesh and Harish cross, Harish returns
Coaches Meher and Meenaxi cross to join their Athletes
Tarun and Meenaxi return
Meenaxi and priyanka cross, Lavesh returns
* All three Coaches are across
Lavesh and Tarun cross, Coach priyanka returns
DONE!

#72 - Triplets Puzzle

Three Brothers are identical triplets. The oldest by minutes is Lavesh, and Lavesh always tells anyone the truth. The next oldest is Tarun, and Tarun always will tell anyone a lie. Harish is the youngest of the three. He sometimes lies and sometimes tells the truth.
Ganpat, an old friend of the family's, came over one day and as usual he didn't know who was who, so he asked each of them one question.
Ganpat asked the brother that was sitting on the left, "Which brother is in the middle of you three?" and the answer he received was, "Oh, that's Lavesh."
Ganpat then asked the brother in the middle, "What is your name?" The response given was, "I'm Harish."
Ganpat turned to the brother on the right, then asked, "Who is that in the middle?" The brother then replied, "He is Tarun."
This confused Ganpat he had asked the same question three times and received three different answers.
Who was who?

View Answer Discuss

The first one cannot be Lavesh, because that would make the first one a liar. The second one cannot be Lavesh for the same reason. So, the third brother must be Lavesh.This means the middle one is Tarun and the only one left is Harish.

#73 -

View Answer Discuss

#74 - Mathematical Symbol Problem

What mathematical symbol can be placed between 5 and 9, to get a number greater than 5 and smaller than 9?

View Answer Discuss

5.9

#75 - Burn The Strings

You have two strings whose only known property is that when you light one end of either string it takes exactly one hour to burn. The rate at which the strings will burn is completely random and each string is different.

How do you measure 45 minutes?

View Answer Discuss

Light both the ends of the first string and one end of the second string. 30 minutes will have passed when the first string is fully burned, which means 30 minutes have burned off the second string. Light the end of the second string and when it is fully burned, 45 minutes will have passed.
Some people have difficulty grasping that when you light both ends of the first fuse, it will take 30 minutes to burn. Because the burning rate is random and unknown to you, you have no idea where the 30 minute mark is on the fuse. If you had an exact duplicate, then the 30 minute mark would be in the same place. It is probably not in the middle, but it is somewhere. If you burn both ends of a fuse it will not stop burning until it has reached this mark, which means 30 minutes is up.

#76 - Gallon-2

You are mixing cement and the recipe calls for five gallons of water. You have a garden hose giving you all the water you need. The problem is that you only have a four gallon bucket and a seven gallon bucket and nether has graduation marks. Find a method to measure five gallons.

View Answer Discuss

Pour the four gallon bucket filled with water into the empty seven gallon bucket. Fill the four gallon bucket up again and poor as much as you can into the seven gallon bucket until the seven gallon bucket is fill. Now there is one gallon left in the four gallon bucket. Empty the seven gallon bucket and transfer the one gallon of water into the seven gallon bucket. Fill the four gallon bucket one more time, then pour the four gallons into the seven gallon bucket making which already has one gallon in it, making a total of five gallons.

#77 - The Islanders

There are two beautiful yet remote islands in the south pacific. The Islanders born on one island always tell the truth, and the Islanders from the other island always lie.
You are on one of the islands, and meet three Islanders. You ask the first which island they are from in the most appropriate Polynesian tongue, and he indicates that the other two Islanders are from the same Island. You ask the second Islander the same question, and he also indicates that the other two Islanders are from the same island.
Can you guess what the third Islander will answer to the same question?

View Answer Discuss

Yes, the third Islander will say the other two Islanders are from the same island.

#78 - Fill the gallon

You have a three gallon and a five gallon measuring device. You wish to measure out four gallons.

View Answer Discuss

Fill the five gallon container. Pour all but two gallons into the three gallon container. Empty the three gallon container. Put the two remaining gallons from the five gallon container into the three gallon container. Fill the five gallon container one more time. Pour one gallon from the five gallon container by filling the three gallon container. Now the five gallon container contains four gallons.

#79 - Old Classical :The missing dollar

Three men in a cafe order a meal the total cost of which is $15. They each contribute $5. The waiter takes the money to the chef who recognizes the three as friends and asks the waiter to return $5 to the men.
The waiter is not only poor at mathematics but dishonest and instead of going to the trouble of splitting the $5 between the three he simply gives them $1 each and pockets the remaining $2 for himself.
Now, each of the men effectively paid $4, the total paid is therefore $12. Add the $2 in the waiters pocket and this comes to $14.....where has the other $1 gone from the original $15?

View Answer Discuss

The payments should equal the receipts. It does not make sense to add what was paid by the men ($12) to what was received from that payment by the waiter ($2)
Although the initial bill was $15 dollars, one of the five dollar notes gets changed into five ones. The total the three men ultimately paid is $12, as they get three ones back. So from the $12 the men paid, the owner receives $10 and the waiter receives the $2 difference. $15 - $3 = $10 + $2

#80 - Boxes with the wrong labels

There are three boxes. One is labeled "APPLES" another is labeled "ORANGES". 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?

View Answer Discuss

Pick from the one labeled "Apples & Oranges". 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 & Oranges"