The total number of 5-digit numbers, formed by using the digits 1, 2, 3, 5, 6, 7 without repetition, which are multiple of 6, is :
Solution
To make a no. divisible by 3 we can use the digits
1,2,5,6,7 or 1,2,3,5,7.<br/><br/>
Using 1,2,5,6,7, number of even numbers is
= 4 × 3 × 2 × 1 × 2 = 48<br/><br/>
Using 1,2,3,5,7, number of even numbers is
= 4 × 3 × 2 × 1 × 1 = 24<br/><br/>
Required answer is 72.
About this question
Subject: Mathematics · Chapter: Permutations and Combinations · Topic: Fundamental Counting Principle
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