4 Maths -- Permutation and Combination

If C(8,r) - C(7,3) = C(7,2) , then r = a. 3 b. 3 or 5c. 5 or 7 d. 7

If C(8,r) - C(7,3) = C(7,2) , then r =

a. 3

b. 3 or 5

c. 5 or 7

d. 7

1 Answers

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