Average of 10 mumbers is 7 . What will be new average if each of numbers is multiplied by 8 ,?

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4.Average

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The average of $10$ mumbers is $7 .$ What will be the new average if each of the numbers is multiplied by $8 \,?$

A

$45$

B

$52$

C

$56$

D

$55$

Solution

The average of $10$ numbers $=7$

Total of $10$ numbers $=10 \times 7=70$

New total of $10$ numbers after each of given

numbers is multiplied by $8=70 \times 8=560$

$\therefore$ New average $=\frac{560}{10}=56$

Standard 13

Quantitative Aptitude

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