An urn contains 5 red and 3 blue balls.In how many different ways,2 red and 1 blue balls can be drawn?
20
10
30
5
Explanation:
The urn contains 5 red and we want 2 red balls.So ways of selecting red balls=$^5C_{2}$= $\dfrac{5\times4}{2\times1}$=10
Similarly the ways of selecting 1 blue ball from 3 blue balls=$^3C_{1}$=$\dfrac{3}{1}$=3
So totoal ways to select 2 red and 1 blue ball will be=$10\times3$=30