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JEE MATHEMATICS MCQ: STATISTICS

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Application +4 | -1

The mean of a set of 30 observations is 75 . If each other observation is multiplied by a non-zero number

\lambda

and then each of them is decreased by 25 , their mean remains the same. The

\lambda

is equal to

View answer and explanation

Correct option: B

\frac{4}{3}

Option B (

\frac{4}{3}

) is correct because setting up the equation for the new mean and solving for

\lambda

gives

\lambda = \frac{4}{3}

.

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