Average of 6 observations is 12 . A new seventh observation is included and new average is decreased

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4.Average

easy

The average of $6$ observations is $12 .$ A new seventh observation is included and the new average is decreased by $1$. The seventh observation is

A

$1$

B

$3$

C

$5$

D

$6$

Solution

Seventh observation

$=7 \times 11-6 \times 12=5$

Standard 13

Quantitative Aptitude

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