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Question
A company has two departments with 42 and 60 employees respectively. Their average weekly wages are Rs. 750 and Rs. 400. The standard deviations are 8 and 10 respectively: Which department has a larger bill?
Solution
For department 1, C.V. = `"SD."/"Mean" xx 100`
= `8/750 xx 100`
= 1.07
Total salary bill = `"n"bar(x)` = 42 x 750 = ₹ 31500
For department 2, C.V. = `"SD."/"Mean" xx 100`
= `10/400 xx 100`
= 2.5
Total salary bill = `"n"bar(x)` = 60 x 400 = ₹ 24000
First department has a larger bill.
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