A brand new Mobile Phone was on sale at 20% as a promotional offer. By what per cent must the Mobile price be increased to sell it at the original price again?

Which tank will fill first?

What is the largest number you can write with just 3 digits?

Most people think of me as money. But when they find me in the water, they won’t get any money out of me. What am I?

How can you make the following equation true by drawing only one straight line: 5+5+5=550 ?

When can we add 2 to 11 and get 1 as the correct answer?

Many have heard it, but nobody has ever seen it, and it will not speak back until spoken to. What is it?

I am a number I am not an odd number I am higher than 90 I am not higher than 100 If you subtract me from 100, you get nothing. What number am I?

Can you think of a smallest +ve number such that if we shuffle the digits of the number, the new number becomes double the original number?

An infinite number of mathematicians are standing behind a bar. The first asks the barman for half a pint of beer, the second for a quarter pint, the third an eighth, and so on. How many pints of beer will the barman need to fulfill all mathematicians' wishes?