Question

The average of a group of 11 numbers is 15. When two new numbers are added to the
group, the new average becomes 25. What is the average of the two numbers added?​

Answer 1

Step-by-step explanation:

y+z/2= 160/2= 80

I hope it helps you

thanks

Answer 2

The average of the two numbers added is 80

Given : The average of a group of 11 numbers is 15. When two new numbers are added to the group, the new average becomes 25.

To find : The average of the two newly added numbers.

Solution :

We can simply solve this mathematical problem by using the following mathematical process. (our goal is to calculate the average of the two newly added numbers)

Average of initially present 11 numbers = 15

Now,

Sum of initially present 11 numbers :

= Average of initially present 11 numbers × Number of numbers in this case

= 15 × 11

= 165

Now, 2 more numbers have been added.

So, new number of numbers = 11 + 2 = 13

New average = 25

New sum of numbers :

= New average × New number of numbers

= 25 × 13

= 325

Now,

New sum of numbers = sum of 11 initially present numbers + sum of 2 newly added numbers = 325

And,

Sum of 2 newly added numbers :

= (Sum of 11 initially present numbers + sum of 2 newly added numbers) - (Sum of 11 initially present numbers)

= 325 - 165

= 160

Average of 2 newly added numbers :

= Sum of 2 newly added numbers ÷ Number of numbers in this case

= 160 ÷ 2

= 80

(This will be considered as the final result.)

Hence, average of two numbers added is 80