Easy math riddles for teens with simple answers

There is a word and six letters it contains. Take one away and twelve is what remains. What word is it?

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?

If you had a pizza with crust thickness 'a' and radius 'z', what's the volume of the pizza?

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

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

Think of a number. Double it. Add ten. Half it. Take away the number you started with. What is your number?

Farmer Brown came to town with some watermelons. He sold half of them plus half a melon and found that he had one whole melon left. How many melons did he take to town?