Question

The mean of $20$ numbers is $17,$ If $3$ is added to each number then the new mean

• A. $10$
• B. $20$
• C. $17$
• D. $15$

Answer 1

Answer: (B)

$20$

The mean of $20$ numbers is $17$

$\therefore$ The sum of $20$ numbers $=20\times 17=340$

$\Rightarrow$ The sum of $20$ numbers after adding $3$ to each number $=(3\times 20)+340=60+340=400$

$\therefore$ Required mean $=\frac{400}{20}=20$