Question

The distance (in km) of 40 engineers from their residence to their place of work were found as follows: 5 3 10 20 25 11 13 7 12 31 19 10 12 17 18 11 32 17 16 2 7 9 7 8 3 5 12 15 18 3 12 14 2 9 6 15 15 7 6 12.

What is the empirical probability that an engineer lives:

(i) less than 7 km from her place of work?

(ii) more than or equal to 7 km from her place of work?

(iii) within km from her place of work?

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Answer 1

$\huge\underline\mathrm{SOLUTION:-}$

The distance (in km) of 40 engineers from their residence to their place of work was found as follows:

5 3 10 20 25 11 13 7 12 31 19 10 12 17 18 11 3 2 17 16 2 7 9 7 8 3 5 12 15 18 3 12 14 2 9 6 15 15 7 6 12

Total numbers of engineers = 40

(i) Number of engineers living less than 7 km from their place of work = 9

The probability that an engineer lives less than 7 km from her place of work =9/40

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(ii) Number of engineers living more than or equal to 7 km from their place of work

= 40 - 9 = 31

The probability that an engineer lives more than or equal to 7 km from her place of work

= 31/40

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(iii) Number of engineers living within 1/2 km from their place of work = 0

The probability that an engineer lives within 1/2km from her place of work = 0/40 = 0

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