In a school, there are four subjects. Seventy percent of students study English, seventy five percent of students study Science, eighty five percent of students study Mathematics and eighty percent of students study Spanish.

Can you calculate the percentage of students that study all four subjects?

Solve the mathematical equation in the picture below.

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?

Analyze and find the missing item in the sequence:
16, 06, 68, 88, __, 98

How many times in a given day, minutes and hour clock comes in a straight line ?

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

Complete the series by replacing "?" with the correct number.

ST ND RD TH '?'

A game is being played where eight players can last for thirty-five minutes. Six substitutes alternate with each player in this game. Thus, all players are on the pitch for the same amount of time including the substitutes.

For how long is each player on the pitch?

What kind of band never plays music?

If a boy blows 18 bubbles,
Then pops 6 eats 7 and then
He pops 5 and blows 1.
How many are left?