Probability of picking 2 red balls and 3 blue?

[r_walid]

There are 5 red balls and 10 blue balls.
if one is to pick 5 balls, What is the probability of picking 2 red and 3 blue?

please explain your reasoning.

[getso]

Is it 400/1001

[raghavakumar85]

Probability = no. of desired outcomes / total no. of outcomes.

no.of desired outcomes = (5c2) x (10c3)
total no. of outcomes = (10+5)c5 = 15c5

Probability = (5c2 x 10c3)/ 15c5 = 400/1001

[m3tm4n]

Hi,

I understand the use of combination formula (easy to solve btw).

But is it possible to solve this problem without using the Combination formula? Just to understand this topic.