Mathematics for IGCSE & O level - Probability (Section 1 - No. 10)
A jar contains 5 red, 7 green, and 3 blue marbles. What's the probability of choosing a red or green marble?
12/15
5/15
7/15
4/5
Paskaidrojums
There are 5 + 7 = 12 red or green marbles out of a total of 15 marbles. Thus, the probability is 12/15 = 4/5