Name a key which is hardest to turn.

Christina, Allison and Lena are 3 daughters of John a well-known Mathematician, When I asked John the age of their daughters. He replied "The current age of her daughters is prime. Also, the difference between their ages is also prime."

How old are the daughters?

A man dies of old age on his 25 birthday. How is this possible?

Look at the below sequence of letters and tell us what the next letter should be:

O T T F F S S ?

John was running from 40 thieves. John has got 3 gold boxes which weigh as 4kg, 2kg, and 1kg respectively. A witty man asked John to stay with him for seven days in exchange for 1kg gold per day. John needs to stay there for seven days and also do not want to give the witty man any advance. How can John pay for his seven days stay?

John’s parents have three sons: Snap, Crackle, and what’s the name of the third son?

What Deficiency does the below rebus represent?

VIT_MIN

Find out the missing number in the picture attached:

How many bananas can you eat if your stomach is empty?

Two fathers and two sons went fishing one day. They were there the whole day and only caught 3 fish. One father said, that is enough for all of us, we will have one each. How can this be possible?