Show all work. Mary purchased a package of 13 different plants, but she only needed 9 plants for planting. In how many ways can she select the 9 plants from the package to be planted?

Question

Show all work. Mary purchased a package of 13 different plants, but she only needed 9 plants for planting.  In how many ways can she select the 9 plants from the package to be planted?

amistre64 · Answer

there are 13 ways to pull out the first plant; that leaves 12 left in the bag

there are 12 ways to pull out the second plant; that leaves 11 left in the bag ... do this 9 times and we get:

13.12.11.10.9.8.7.6.5  different ways

amistre64 · Answer

13 P 9

P(13,9)

13!/8!

many ways to notate it

amistre64 · Answer

that last bit was off; should be 13!/4!  :)

anonymous · Answer

that make sense