See ValliRam's answer to Xiaoshang Li's Primary 6 Maths question

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Date Posted: 7 years ago

Clifton Ng Wei Zhi

7 years ago

nCr should be n!/((n-r)!*r!) not n!/(n-r)!.

So 8C2 should be 8!/(6!*2!) = (8*7)/2 = 28, not 56.