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

You are playing a game with your friend Jack. There are digits from 1 to 9. You both will take turn erasing one digit and adding it to your score. The first one to score 15 points will win the game.

Would you want to play first or second?

PS: The sum should be exactly 15.

A seven-year-old kid challenged his classmates that he can make the number one disappear by adding something to it.

How can he do that?

Can you calculate the probability of getting a sum of six when a dice is thrown twice?

It's a test that will check your IQ.

Suppose you have one 11 minute hourglass and one 13 minute hourglass.

Can you measure exactly fifteen minutes using them ?

I have a clock(12-hour format) and both the needles of the clock overlap at 12:00.
After how much time, they will overlap again?

Can you find the missing piece of the Porsche?

How can one talk without saying a single word?

How much will a 38° angle measure when looked at under a microscope that magnifies ten times?

Begin with a word, five letters to my name,
Remove the first and last but I am the same
Take out my middle and still, I remain.
What word am I?