NCERT Solutions
Class 9 Maths
Probability

Ex.15.1 Q.8
Refer to Q.2, Exercise 14.2. What is the empirical probability that an engineer life:
(1) less than 7 km from her place of work?
(2) more than or equal to 7 km from her place of work?
(3) within km from her place of work?
Total number of engineers = 40
Let us arrange the data in ascending order as follows:
2, 2, 3, 3, 3, 5, 5, 6, 6, 7, 7, 7, 7, 8, 9,9,10, 10, 11, 11, 12, 12, 12, 12, 12, 13, 14, 15, 15, 16, 17,
17, 18, 18, 19, 20, 25, 31, 32
(1) P (an engineer lives less than 7 km from her place of work)
= Number of engineer lives less than 7 km from her place of work/Total no. of engineer
=
(2) P (an engineer lives more than or equal to 7 km from their place of work)
= engineer lives more than or equal to 7 km from their place of work /Total no. of engineer
=
(3) P (an engineer lives within km from her place of work)
= Number of engineer lives within km from her place of work/Total no. of engineer
= = 0
Note: Questions 9 and 10 are activities, so student should perform it on their own.