JEE MATHEMATICS MCQ: STATISTICS

1 Easy

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Application +4 | -1

The first of two samples has 100 items with mean 15 and

SD = 3.

If the whole group has 250 items with mean 15.6 and

SD = \sqrt {13.44}

, the SD of the second group is

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Correct option: A

Option A (4) is correct because it is the standard deviation of the second group calculated using the given information about the combined group and the first group.

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