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The number of observation in a group is ...

The number of observation 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

6

D

8

Text Solution

Verified by Experts

The correct Answer is:
B
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