Given a group of
n object. We want to make a selection of
k objects out of the n object. This can be done in
C(n, k) many ways, where

,
where k!=1*2*3*...(k-1)*k
Thus, we can do the selection of 3 cd's out of 5, in C(5,3) many ways,
where

Answer: 10
Answer:
150
Step-by-step explanation:
Answer:
I sorted them by colors: red goes with red, blue with blue, purple with purple and brown with brown :))
Step-by-step explanation:
Wx+yz=bc
-yz. -yz
Wx=bc-yz
Wx/W=bc-yz/W
x=bc-yz/W