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If .^(n)C(r - 1) = 28, .^(n)C(r) = 56 an...

If `.^(n)C_(r - 1) = 28, .^(n)C_(r) = 56 and .^(n)C_(r + 1) = 70`, then the value of r is equal to

A

6

B

2

C

3

D

4

Text Solution

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The correct Answer is:
C
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