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JEE MATHEMATICS MCQ: COMBINATIONS

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Application +4 | -1

Let

A

be the set of 4 -digit numbers

a_{1} a_{2} a_{3} a_{4}

where

a_{1} > a_{2} > a_{3} >

a_{4}

. Then

n(A)

is equal to

View answer and explanation

Correct option: C

210

Option C (210) is correct because any selection of four digits from the ten digits gives one such number.

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n