7boy average is 15year if 1 boy included so new average is 16year so find the age of new boys
Answers
Here's your answer :-
Average of the age of the 7 boys = 15 years
Sum of the age of 7 boys = 15 × 7 = 105 years.
When 1 new boy is added, the average of the age of 8 boys become = 16 years.
Sum of the ages of the 8 boys = 16 × 8 = 128 years.
Thus, the age of the new boy = 128 - 105 = 23 years.
Number of boys = 7
Average = 15 years
Average = sum of ages of 7 boys
number of boys
sum of ages of 7 boys = Average × number of boys
= 15 × 7
= 105
Given New Average = 16 years
New Average = sum of age of 7 boys + age of new boy
number of boys + 1 new boy
16 = 105 + age of new boy
7 + 1
16 = 105 + age of new boy
8
105 + age of new boy = 16 × 8
105 + age of new boy = 128
age of new boy = 128 - 105
Age of new boy = 23 years