Question

A bag contains 7 green balls and 3 white balls.

A ball is drawn from the bag and replaced,

before a second draw is made. What is the

probability that: (a) they are both white (b) one

is white one is green​

Answer 1

10 balls in total therefore

A) chance of being white is 3/10

Chance twice: 3/10

Both white = 3/10 x 3/10 = 9/100

B) 3/10 x 7/10 = 21/100

Answer 2

10 total balls.

A) first pick white = 3/10

Second pick white = 3/10

Both white = 3/10 x 3/10 = 9/100

B) 3/10 x 7/10 = 21/100