Question

A box contains 3 red balls, 5 white balls, and 10 green balls. If a ball is chosen at random what is the probability that it is either white or green?
A. 5
B. 3/10
C. 5/6
D. 1/2

Answer 1

18 balls in total

Answer 2

15 balls that are either white or green

Answer 3

...

Answer 4

Right I am thinking it is C but I just want to double check probability is not my strong point

Answer 5

P(W or G)= P(W)+P(G)-P(W and G)

since a ball can't be both, P(W and G)=0 (mutually exclusive events).

Answer 6

Yes i believe you're correct

Answer 7

what's P(W)?

Answer 8

15/18 = 5/6

Answer 9

10 Green Balls

5 White Balls

10 + 5 = 15

18 in total.

15/18 = 5/6

Answer 10

1-P(W or G) = P(R) = 1- 3/18 = 1 - 1/6 = 5/6