Mathematics for IGCSE & O level - Probability (Section 7 - No. 23)
A bag contains 5 red, 7 blue and 3 green marbles. What is the probability that a marble chosen at random is not green?
3/15
12/15
5/15
7/15
คำอธิบาย
There are 12 marbles that are not green (5 red + 7 blue) out of 15 total marbles. Therefore, the probability is 12/15.