CAT 2020 Number System Question (Medium)

Question

How many of the integers 1, 2, , 120, are divisible by none of 2, 5 and 7?

Accepted Answer

Step 1 We are asked to count how many numbers from 1 to 120 are not divisible by 2, 5, or 7. Use the Inclusion-Exclusion Principle to count how many are divisible by at least one of them, then subtract from 120. Let - A numbers divisible by 2 120 2 60 - B numbers divisible by 5 120 5 24 - C numbers

CAT 2020

Quantitative

Number System

Medium

How many of the integers 1, 2, … , 120, are divisible by none of 2, 5 and 7?

Master Your PI Skills for Top B-Schools!

Practice

Features

Support