Mathematics for IGCSE & O level - Probability (Section 5 - No. 11)
A bag contains 3 red, 4 yellow, and 2 green marbles. What is the probability of selecting a red or yellow marble?
3/9
7/9
4/9
2/9
คำอธิบาย
There are 3 red + 4 yellow = 7 favorable outcomes out of 9 total marbles. P=7/9.