Using four sevens (7) and a one (1) create the number 100. Except for the five numerals, you can use the usual mathematical operations (+, -, x, :), root and brackets ()

Look at the below sequence of letters and tell us what the next letter should be:

O T T F F S S ?

A man who was outside in the rain without an umbrella or hat didn’t get a single hair on his head wet. Why?

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?

Can you find out the missing number?

? 4 5 3 5

9 5 7 10 3

What do you see in the image below

After teaching his class all about Roman numerals (X = 10, IX=9 and so on) the teacher asked his class to draw a single continuous line and turn IX into 6. The teacher's only stipulation was that the pen could not be lifted from the paper until the line was complete.

You are mixing a mixture of cement and Sand with five gallons of water. You have a garden hose giving you all the water you need. The problem is that you only have a four-gallon bucket and a seven-gallon bucket and neither has graduation marks. Find a method to measure five gallons.

Find the missing number in the image below.

A man dies of old age on his 25 birthday. How is this possible?