Question

The average age of boys in class is 15.5 years, while girls average age is 16.5 years. the average agevofvtotal students is 16 years. if there are 30 boys innclass then how many girls ?

Answer 1

Step-by-step explanation:

Average age of boys in a class is 15.5 years.

Average age of girls is 16.5 years.

There are 30 boys in class.

Let X be the total age of boys .

so X/30=15.5

=X=15.5*30=465

Let y be the total age of girls in a class and z be their numbers.

so, X+y /30+z=16

465+y =16*30+z

465+y=480+16z

y-16z=480-465=15

Now y/z=16.5

y=16.5z

putting the value of y in above equation we get

16.5z-16z=15

0.5z=15

z=15*0.5=30

Hence the number of girls in class is 30.