A bag contains 3 red counters and 5 blue counters, and one counter is taken at random. What is the probability that the counter is not red? Give the probability as a fraction out of the total number of counters.

Explanation

Five of the eight counters are not red, so five draws in eight succeed, and the same figure appears if the probability of red is taken away from a whole. Answering 3/5 measures the two colours against each other, so it is not the probability of any draw from this bag, because the whole here has to be all 8 counters.