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The number of observations in a group is...

The number of observations in a group is 40. If the average of first 10 is 4.5 and that of the remaining 30 is 3.5, then the average of the whole group is

A

`1/5`

B

`15/4`

C

4

D

8

Text Solution

Verified by Experts

The correct Answer is:
B
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