Question

An organisation selected 2400 families at random and surveyed them to determine a relationship between income level and the number of vehicles in a family. The information gathered is listed in the table below Monthly Income (in Rs.) Vehicles per family 0 1 2 Above 2 Less than 7000 10 160 25 0 7,000 – 10,000 0 305 27 2 10,000- 13,000 1 535 29 1 13,000- 16,000 2 469 59 25 16,000 or more 1 579 82 88 Suppose a family is chosen. Find the probability that the family chosen is (i) earning Rs. 10000 – 13000 per month and owning exactly 2 vehicles. (ii) earning Rs. 16000 or more per month and owning exactly 1 vehicle. (iii) earning less than Rs. 7000 per month and does not own any vehicle. (iv) earning Rs. 13000 – 16000 per month and owning more than 2 vehicles. (v) owning not more than 1 vehicle. Select the correct answer from above options

Answer 1

Total number of families surveyed = 2400 ∴ n(S) = 2400 (i) earning Rs. 10000 – 13000 per month and owning exactly 2 vehicles = 29 ∴ n(A) = 29 (ii) earning Rs. 16000 or more per month and owning exactly 1 vehicle = 579 ∴ n(B) = 579 (iii) earning less than Rs. 7000 per month and does not own any vehicle =10 ∴ n(C) = 10 (iv) earning Rs. 13000 – 16000 per month and owning more than 2 vehicles = 25 ∴ n(D) = 25 (v) owning not more than 1 vehicle 10 + 0 + 1 + 2 + 1 + 160 + 305 + 535 + 469 + 579 = 2062 ∴ n(E) = 2062