Question

The average age of a,b and c is 40 years. If the age of b is (9/10) of this average, what is the average age of a and c together?

Answer 1

Answer:

Step-by-step explanation:

Dear friend, this is the answer..

GIVEN

average age of a,b,c = 40 yrs

age of B = (9 / 10) of 40

              = 36 yrs

SO,

(a+b+c)/3 = 40             (given average)

= (a+36+c) / 3 = 40

= (a + 36 +c) = 120        (transferred 3 to rhs)

= (a + c) =  84               (transferred 36 to rhs)

SO TOTAL OF AGES OF a AND c is 84

THEREFORE,

AVERAGE AGE OF a AND c = (a +c) / 2

                                               =  84 / 2           (from above a+c = 84)

                                                = 42 yrs is the average age of a and c