I am an odd number. Take away a letter and I become even. What number am I?

Using Only Five 5's and any mathematical operator make sum as 37

If 5 cats catch 5 mice in 5 minutes, how long will it take one cat to catch a mouse?

How many pluses should we put between the digits of 987654321 to get a total of 99, and where?

There is a number which when you multiply by 3 and subtract 2 from the result, then the resulting number is the reverse of the actual number.

What is the smallest number that stands true on the statement?

There is a square of a particular number which when doubled, becomes 7 more than its quarter.

Can you find the number?

John went to buy some expensive, foreign chocolates. He only had Rs 100 with him. When he reached the shop, he got out and know that on those chocolates, there was a 15% import duty and 5% VAT.

How much worth chocolate should he buy so that he can accommodate it in Rs 100?

A man has eighty-one cows ( numbered 1,2,3...81 as such). The beauty is that cow no. 1 gives 1ltr of milk, cow no. 2 gives 2ltrs of milk and so on. The man wants to equally distribute the cows among his nine sons so that each one of them gets the same quantity of milk.

John replied, when asked how old he was. In 2 years he will be twice as old as he was five years ago.' How old is he ?

Below, you will find the mathematical proof that 10 equals 9.99999?. But is that possible or there is something wrong about it? Can you find the error?

x = 9.999999...
10x = 99.999999...
10x - x = 90
9x = 90
x = 10