Mathematics for IGCSE & O level - Probability (Section 3 - No. 33)

A box contains 20 marbles: 8 are red, 7 are blue, and 5 are green. What is the probability of selecting a red marble?

2/5

7/20

1/4

4/5

There are 8 red marbles out of 20 total. 8/20 simplifies to 2/5, also written as 40%