The average of a set of 15 observations is recorded, but later it...

The average of a set of 15 observations is recorded, but later it is found that for one observation, the digit in the tens place was wrongly recorded as 8 instead of 3. After correcting the observation, the average is

Options

A $reduced by \frac{1}{3}$
B $increased by \frac{10}{3}$
C $reduced by \frac{10}{3}$
Dreduced by 50

Correct answer

C. $reduced by \frac{10}{3}$

Step-by-step solution

Sum of 15 observations

=15 \times A

(where

A

is average) Reduce in value after correction.

8 x-3 x=50\{

where

x=

unit digit of wrong number \}

\therefore

Reduction in new average

=\frac{50}{15}=\frac{10}{3}

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