Video Transcript
Which of the following is equal to
41 πΆ five? Is it (A) 41 π five divided by five
factorial, (B) 41 π five divided by five, (C) 41 π five multiplied by five
factorial, or (D) 41 π five multiplied by five?
We begin by recalling our formulae
for permutation and combination. The permutation πππ is equal to
π factorial divided by π minus π factorial. And the combination ππΆπ is equal
to π factorial divided by π minus π factorial multiplied by π factorial. Combining these two formulae, we
see that ππΆπ is equal to πππ divided by π factorial. In this question, π is equal to 41
and π is equal to five. This means that 41 πΆ five is equal
to 41 π five divided by five factorial. The correct answer is therefore
option (A).
