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JEE MATHEMATICS MCQ: PERMUTATIONS

1 Easy

1 of 1

Application +4 | -1

If

{ }^{12} {P}_{{r}}-{ }^{11} {P}_6+6 .{ }^{11} {P}_5

, then

{r}

is equal to:

View answer and explanation

Correct option: A

6

Option A (6) is correct because

{ }^{12} {P}_{{r}}={ }^{11} {P}_6+6 .{ }^{11} {P}_5

simplifies to

{ }^{12}P_r = { }^{12}P_6

, thus

r=6

.

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