10+10 and 11+11 can give you the same answer.

Explain how?

A Scientist was fifty years old in the year 2000 but he was forty years old in the year 2010. How can this be possible?

PS: It has a logical answer.

John was gifted a new Hayabusa. He drove x miles at 55mph. Then he drove x+20 miles at 40mps. He drove his bike for 100 minutes. How much distance did he travel?

There is a basket full of hats. Three are white and two are black. Three men, Tom, Tim, and Jim, each take a hat out of the basket and put it on their heads without seeing the hat they selected or the hats the other men selected. The men arrange themselves so Tom can see Tim and Jim’s hats, Tim can see Jim’s hat, and Jim can’t see anyone’s hat. Tom is asked what color his hat is and he says he doesn’t know. Tim is asked the same question, and he also doesn’t know. Finally, Jim is asked the question, and he does know. What colour is his hat?

Why did the Girl throw the butter out of the window?

Which is faster, Heat or Cold ? Explain.

I am the beginning of everything, the end of everywhere. I'm the beginning of eternity, the end of time and space. What am I?

You have a three-gallon and a five-gallon measuring device. You wish to measure out four gallons.

Place a mathematical symbol between the numerals 5 and 9 in such a way that the resulting number is greater than 5 but smaller than 9.

How can you drop a raw egg from a height onto a concrete floor without cracking it?