Saved Bookmarks
| 1. |
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 :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. |
|
Answer» Total no. of families considered = 2400 (i) P(a family earning Rs 10000 – 13000 per month and owning exactly 2 vehicles) = No. of families earning Rs 10000 – 13000 per month and owning 2 vehicles /Total no. of families = 29 / 2400 (ii) P (a family earning Rs 16000 or more per month and owning exactly 1 vehicle) = No. of families earning Rs 16000 or more per month and owning 1 vehicle/ Total no. of families = 579/ 193 = 2400/ 800 (iii) P(a family earning less than Rs 7000 per month and does not own any vehicle) = No. of families earning less than Rs 7000 per month and does not own any vehicle /Total no. of families = 10 / 2400 = 1 / 240 (iv) P(a family earning Rs 13000 – 16000 per month and owing more than 2 vehicles) = No. of families earning Rs 13000 – 16000 per month and owning more than 2 vehicles / Total no. of families = 25/ 2400 = 1 /96 (v) P (a family owning 0 vehicle or 1 vehicle) = P (a family not owning more than 1 vehicle) = (10 +0+ 1+ 2+ 1+ 160+ 305+ 535+ 469+ 579) / 2400 = 2062 / 2400 = 1031/ 1200 |
|