Maths Set Theory Puzzle

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?




Similar Math Riddles

In a stable, there are men and horses. In all, there are 22 heads and 72 feet. How many men and how many horses are in the stable

Asked by Neha on 29 Jun 2023


There once were seven dwarfs who were all brothers. They were all born two years apart. The youngest dwarf is seven years old. How old is his oldest brother?

Asked by Neha on 13 Jun 2025

In a basket of apples,
when counted in twos, there was one extra
when counted in threes, there were two extra when counted in fours, there were three extra
when counted in fives, there were four extra
when counted in sixes, there was five extra.

However, if the apples were counted in sevens, no extra apple was left. Can you calculate the minimum number of apples that were present in the basket?

Asked by Neha on 12 Sep 2023


James ordered a fishing rod, priced at $3.56. Unfortunately, James is an Eskimo who lives in a very remote part of Greenland and the import rules forbid any package longer than 4 feet to be imported. The fishing rod was 4 feet and 1 inch, just a little too long, so how can the fishing rod be mailed to James without breaking the rules? Ideally James would like the fishing rod to arrive in one piece!

Asked by Neha on 11 Apr 2022

We know that the number 7 is the prime followed by a cube. Which next number is also a prime followed by a cube?

Asked by Neha on 05 Apr 2026

Can you make numbers like 24, using numbers 3,3,7 & 7 with any arithmetic operator?

Asked by Neha on 25 Feb 2023


A man had five children. He had $100 with him to give to his children. He decided to start with the youngest child and then give $2 more than each younger child to his next elder child.

For example, if he gives $x to the youngest child, he will give $(x+2) to the next one, $[(x+2) + 2] to the next one and so on.

Can you find out how much did the youngest one receive?

Asked by Neha on 30 Sep 2024

What three numbers, none of which is zero, give the same result whether they’re added or multiplied?

Asked by Neha on 26 Feb 2022

Our product and our sum always give the same answer. Who are we?

Asked by Neha on 11 Oct 2021


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

Asked by Neha on 02 Apr 2022

Hot Articles

Amazing Facts

Out of the Box

The phrase “thinking outside the box” was popularised from the solution to a topographical puzzle involving 9 dots in a box shape.