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 ()

Can you write down eight eights so that they add up to one thousand?

You have two buckets of 11 liters and 6 litres.
How can you measure exactly 8 litres?

Can you make the below equation true by using any three numbers from "1, 3, 5, 7, 9, 11, 13 and 15"?

( ) + ( ) + ( ) = 30

The doctor advised his patient to take a tablet after every fifteen minutes. He gave him five tablets in total.

How much time will he take to have all the five tablets?

There are five vowels (a, e, i, o, u) in the English language.
Can you tell us a word that contains all these vowels?

You can hear me, but you can't touch or see me.

What am I?

Identify the hidden meaning behind this picture?

What has to be broken before you can use it?

If we tell you that there is a relation between the numbers and letters in the given figure, can you analyze it and find the missing letter in the last box?