Question

Assume that there are 19
frozen dinners: 9 pasta, 7 chicken, and 3 seafood
dinners. The student selects 5 of them.


What is the probability that at least 2 of the dinners
selected are pasta dinners?

Answer 1

This is a pretty tough problem.

Answer 2

First you want to find how many dinners are possible in total.

Answer 3

Ok so heres what we will do

5 dinners can be selected from 19 in 19C5 ways

now lets say event A = ATLEAST 2 are pasta

so lets write the cases
1) 2 pasta + 3 chicken = 9C2*7C3
2) 2 pasta + 3 seafood
3) 2 pasta + 1 chicken + 2 seafood
4) 2 pasta + 2 chicken+1 seafood
5) 5 pasta
6) 3 pasta +1 chicken +1 seafood
7) 3 pasta + 2chicken
8) 3 pasta + 2seafood
9) 4 pasta+1 chicken
10) 4 pasta+1 seafood

probabllity of event A= add all these independent cases

i have given you the idea, do some work