The number of 3 digit numbers ' $a b c$ ' such that $b < c$ is

JEE MATHEMATICS MCQ: PERMUTATIONS

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The number of 3 digit numbers '

a b c

' such that

b < c

View answer and explanation

Correct option: B

405

Option B (405) is correct because there are 9 choices for the first digit and then the number of ways to choose the second and third digits such that b < c is the sum of integers from 1 to 9.

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