When Jack was six years old he hammered a nail into his favourite tree to mark his height. Ten years later at age sixteen, Jack returned to see how much higher the nail was. If the tree grew by five centimetres each year, how much higher would the nail be?

We can be boring,Or interesting.
We can be long,Or short.
We can have pictures,Or just words.
Many love us,But many also hate us.
What are we?

You walk into a room that contains a match, a kerosene lamp, a candle and a fireplace. What would you light first?

You have to put a letter on the following to make it a meaningful word. The only challenge is that you can't use 'E'.

S E Q U E N C _

There was a man he lives in a hotel each morning he presses the first floor button each evening if there is a person in the elevator he asks him to press the 10 floor button if there is no one in the elevator he takes the stairs why.

What is the four-digit number in which the first digit is one-third the second, the third is the sum of the first two, and the last is three times the second?

Three fair coins are tossed in the air and they land with heads up. Can you calculate the chances that when they are tossed again, two coins will again land with heads up?

Find the smallest sentence with all the English alphabet.

People make me, save me, change me, raise me. What am I?

I am a seven-letter word but if you remove four of my letters I will have one left. What word am I?