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JEE MATHEMATICS MCQ: COMBINATIONS

1 Easy

1 of 1

Application +4 | -1

If

{\;^8}{C_r} - {\;^7}{C_3} = {\;^7}{C_2}

, then

r

is equal to

View answer and explanation

Correct option: A

3

Option A (3) is correct because solving the given combinatorial equation using the combination formula leads to r = 3.

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n