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MathsMediumMCQ2020 · 02 Sep Shift 1

Q58.Let X = {x ∈N : 1 ≤x ≤17} and Y = {ax + b : x ∈X and a, b ∈R, a > 0} . If mean and variance of elements of Y are 17 and 216 respectively then a + b is equal to (1) 7 (2) −7 (3) −27 (4) 9

What This Question Tests

This question tests the properties of mean and variance under a linear transformation, requiring the student to correctly apply the formulas to find the original mean and variance and then solve for the transformation parameters.

Concepts Tested

MeanVarianceLinear Transformation of Data

Formulas Used

Mean(ax+b) = a*Mean(x) + b

Variance(ax+b) = a²*Variance(x)

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