Question

The table given below shows the ages of 75 teachers in a school. Age (in years) 18-29 30-39 40-49 50-59 Number of teachers 3 27 37 8 A teacher from this school is chosen at random. What is the probability that the selected teacher is (i) 40 or more than 40 years old? (ii) of any age lying between 30-39 years (including both)? (iii) 18 years or more and 49 years or less? (iv) 18 years or more old? (v) above 60 years of age? Select the correct answer from above options

Answer 1

It is given that Total number of teachers = 75 (i) We know that Probability that the selected teacher is 40 or more than 40 years old = (37 + 8)/ 75 So we get Probability that the selected teacher is 40 or more than 40 years old = 45/75 = 3/5 (ii) We know that Probability that the selected teacher is of any age lying between 30-39 years (including both) = 27/75 So we get Probability that the selected teacher is of any age lying between 30-39 years (including both) = 9/25 (iii) We know that Probability that the selected teacher is 18 years or more and 49 years or less = (3 + 27 + 37)/ 75 So we get Probability that the selected teacher is 18 years or more and 49 years or less = 67/75 (iv) We know that Probability that the selected teacher is 18 years or more old = (3 + 27 + 37 + 8)/75 So we get Probability that the selected teacher is 18 years or more old = 75/75 = 1 (v) We know that Probability that the selected teacher is above 60 years of age = 0/75 = 0