Question

average of 3 numbers is 15. If each number is increased by 5. what is the average of the new 3 numbers​

Answer 1

SOLUTION

The average of 3 numbers is 15 .

$\sf Average = \dfrac{Sum \: of \:the \: Numbers }{Total \: Number \:of \: Numbers}$

Here ,

$\sf \dfrac{Sum \: of \:the \: Numbers }{3} = 15$

Let us Assume that the sum of the numbers is ' x '  ,

Therefore ,

$\dfrac{x}{3} = 15$

$\implies$ x = 15× 3 = 45

So , if each number is increased by 5 , then the new sum of the numbers will be = x + (3×5) = x + 15

Here, x = 45

∴ The sum of new numbers = 45 + 15 = 60

We know that ,

$\sf Average = \dfrac{Sum \: of \:the \: Numbers }{Total \: Number \:of \: Numbers}$

∴ Average =

$\sf \dfrac{60}{3} = \underline{\underline{{20}}}$

$\sf \red \boxed { Average \:of \: new \: 3 \:numbers = 20 }$