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MathsMediumMCQ2019 · 08 Apr Shift 2

Q74.A student scores the following marks in five tests: 45,54,41,57,43. His score is not known for the sixth test. If the mean score is 48 in the six tests, then the standard deviation of the marks in six tests is: 10 100 (1) (2) 3 3 (3) 10 (4) 100 √3 √3

What This Question Tests

This problem tests the calculation of the mean and standard deviation for a set of data. It first requires finding an unknown data point using the mean, then applying the standard deviation formula.

Concepts Tested

Mean of ungrouped dataStandard deviation of ungrouped data

Formulas Used

Mean = (Σxi) / n

Standard Deviation σ = sqrt(Σ(xi - μ)^2 / n)

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