Practise the method.Example 1A bag contains 7 red and 2 blue counters. One counter is chosen at random. What is the probability it is red?Show worked answerAnswer: 977 of the 9 equally likely counters are red.97.Example 2A bag contains 8 red, 2 blue and 5 green counters. One is chosen at random. What is the probability it is not red?Show worked answerAnswer: 157Blue or green gives 7 favourable counters out of 15.157.Example 3Tickets numbered 1 to 13 are equally likely to be chosen. What is the probability of choosing a multiple of 5?Show worked answerAnswer: 132There are 2 multiples of 5 from 1 to 13.Probability =132.