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A Class of 40 students is divided into f...

A Class of 40 students is divided into four groups named as A, B, C and D. Group-wise percentage of marks scored by them are given below in the table.
`{:(A,B,C,D),(20,42,10,21),(30,51,25,69),(40,45,85,70),(25,58,73,86),(22,53,98,53),(45,64,43,68),(65,72,64,99):}`
By using the coefficient of range find which of the group has shown good performance.

A

A

B

B

C

C

D

D

Text Solution

Verified by Experts

The correct Answer is:
B
(i) Find the coefficient of range of A, B, C and D and compare.
(ii) `"Coefficient of range" = ("Maximum value - Minimum value")/("Maximum Value + Minimum value")`
(iii) Find the coefficient of range of A, B, C and D.
(iv) The least coefficient of range implies good perfprmance.
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Knowledge Check

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