Question

Use Pascal’s triangle to find the number of ways to choose 5 shirts from 7 shirts.
a.
6
c.
21
b.
56
d.
none of these

Answer 1

the bottom row on the second triangle is the 7th level
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Answer 2

and your answer is highlighted in dark blue

Answer 3

This can be verified by \[\left(\begin{matrix} 7\\ 5\end{matrix}\right)\]

Answer 4

Which is the same as \[\frac{ 7! }{ 5! \times (7-5)! } = 21\]