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 Riddles

I am not alive, but I grow; I don't have lungs, but I need air; I don't have a mouth, but water kills me. What am I?

Asked by Neha on 14 May 2021


I left my campsite and hiked south for 3 miles. Then I turned east and hiked for 3 miles. I then turned north and hiked for 3 miles, at which time I came upon a bear inside my tent eating my food! What colour was the bear?

Asked by Neha on 03 Jul 2025

Which English verb becomes past tense just by rearranging the letters?

Asked by Neha on 07 Sep 2025


You are given a cube that is made with the help of 10x10x10 smaller cubes summing up to a total of 1000 smaller cubes. You are asked to take off one layer of the cubes.
How many remain now?

Cube Game

Asked by Neha on 17 Jan 2021

Why is the Hole below a Lock?

The Hole below a Lock

Asked by Neha on 22 Jul 2023

Consider this: Arnold Schwarzenegger has a big one. Michael J. Fox has a small one. Prince doesn’t have one. The Pope has one but never uses it. Bill Clinton has one and uses it all the time. What is it?

Asked by Neha on 29 Jun 2025


There's one "sport" in which neither the spectators nor the participants know the score or the leader until the contest ends.

What is it?

Asked by Neha on 10 Apr 2022

What does the below rebus puzzle mean?

Funny House Riddle

Asked by Neha on 19 Mar 2026

You and your two friends are working in a multinational company. How can you three find out the average salary of you all without disclosing your own salary to the other two?

Asked by Neha on 26 Nov 2025


In the following series, a set of numbers is progressing with a particular pattern. Can you deduce that pattern and find the missing set?

(2 + 6), (21 + 6), (58 + 6), (119 + 6), ___

Asked by Neha on 05 Dec 2025

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.