Answer:
3/50
Step-by-step explanation:
P( 1st ball is a black ball) = number of black balls/ total balls
= 2/10 = 1/5
We put the ball back so we still have the same number of balls
P( 2nd ball is a red ball) = number of red balls/ total balls
= 3/10
P (1st ball black, 2nd red) = P( 1st ball is a black ball)* P( 2nd ball is a red ball)
=1/5* 3/10
= 3/50