Question

PART-A (
MATHEMATICS)
1) The average age of a class is 19years. While the average age of girls is 18 and that of boys is
21. If the number of girls in the class is 16, find the number of boys in the class?​

Answer 1

Answer:

total of ages of girls

=18*16=288

if there are b boys in class,

total of their ages is

b*21

Step-by-step explanation:

total of ages of all boys and all girls=288+21b

and average age of whole class is

19=(21b+288)/(16+b)

so19*16+19b=21b+288

or 304-288=21b-19b

so 16= 2b

so b=8 or

ANSWER 8 boys