What is the next number in the series?

15 29 56 108 208 ?

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?

If 21x = 79x, what is the value of x?

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

What is the riddle which can be asked all day with a different correct answer each time.

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?

How is a fly different from a mosquito?

What do you see in the image below

Do You See It?

What can you deduce from the following BrainBat?

CRY
LMKI