Before Mount Everest was discovered, what was the highest mountain in the world?

If it took eight men ten hours to build a wall, how long would it take four men to build it?

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

I am the fastest animal but cannot climb the tree. What am I?

You have four chains. Each chain has three links in it. Although it is difficult to cut the links, you wish to make a single loop with all 12 links. What is the fewest number of cuts you must make to accomplish this task?

Solve the equation in the image by looking at the pattern closely.

I’m tall when I’m young, and I’m short when I’m old. What am I?

A sundial has the fewest moving parts of any timepiece. Which has the most?

How many times in a given day, minutes and hour clock comes in a straight line ?

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?