Arithmetic mean of 100 observations is 24.6 is added to each of observations and, then each of them

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4.Average

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The arithmetic mean of $100$ observations is $24.6$ is added to each of the observations and, then each of them is multiplied by $2.5 .$ Find the new arithmetic mean.

A

$30$

B

$75$

C

$35$

D

$60$

Solution

On adding $6,$ arithmetic mean $=24+6=30$

On multiplying by $2.5,$ arithmetic mean $=30 \times 2.5=75$

Standard 13

Quantitative Aptitude

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