Question

Four red balls are numbered from $1$ to $4$ and three blue balls are numbered from $3$ to $5$. If these balls are placed in a bag and a ball is drawn from a bag, what is the probability of choosing a red ball and a blue ball numbered $5$?

Answer 1

Given,

4 red balls, 3 blue balls.

Therefore the probability of choosing a red ball $=\frac{1}{4+3}=\frac{1}{7}$

Total of blue balls 3, numbered from 3,4,5.

Therefore the probability of choosing a 5 numbered blue ball $=\frac{1}{1+1+1}=\frac{1}{3}$