CAT 2020 Number System Question (Medium)

Question

How many integers in the set 100, 101, 102, ..., 999 have at least one digit repeated?

Optima Learn · Accepted Answer

We are asked How many 3-digit numbers from 100 to 999 have at least one repeated digit? Step 1 Total 3-digit numbers From 100 to 999 Total 999 100 1 900 Step 2 Count how many have all distinct digits - Hundreds digit 1 to 9 9 options - Tens digit 0 to 9 excluding the hundreds digit 9 options - Units

CAT 2020 Number System — Previous Year Question

CAT 2020

Quantitative

Number System

Medium

Ready for IIM Interview Questions?

Practice

Features

Support