Why Aeroplane windows are round?

Arrange the numbers 1, 2, 3, 4, 5, 6, 7, 8 and 9 above and below the division line in a manner that the thus formed fractions equal to 1/3.

(You can use one number only once)

If you toss a coin 10 times and it lands heads up every time, what are the chances it will land heads up if you toss it again?

There is a box. The area of its top is 240 square units, the area of the front is 300 square units and the area of the end is 180 square units.

Can you calculate the dimensions of this box with the given data?

John bought 150 chocolates but he misplaced some of them. His Father asked him how many chocolates were misplaced.
He gave the following answer to him:
If you count in pairs, one remains
If you count in threes, two remain
If you count in fours, three remain
If you count in fives, four remain
If you count in sixes, five remain
If you count in sevens, no chocolate remains.

Can you analyze the statements and tell us how many chocolates were lost?

What does does this rebus picture means ?

As easy as you can get into me, it is as hard to get out of me.

Do you know what I am?

Why is it very easy to weigh a fish?

What has 88 keys?

By removing one matchstick and adding one matchstick, can you convert the word "ZOO" to an animal name?