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For a group of 50 male workers, the mean...

For a group of 50 male workers, the mean and the standard deviation of their daily wages are Rs. 630 and Rs. 90 respectively and for a group of 40 female workers these are Rs. 540, and Rs . 60 respectively. Then, the standard deviation of all these 90 workers is

A

60

B

70

C

80

D

90

Text Solution

Verified by Experts

The correct Answer is:
D
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