A family consists of two grandparents, two parents and three grandchildren. The average age of the grandparents is 67, that of the parents is 35 years and that of the grandchildren is 6 years. What is the average age of the family? A. 28 4/7 years B. 31 5/7 years C. 32 1/7 years D. 35 years

Sagot :

Getting the sum of all their ages you'll have:
67(2) + 35(2) + 6(3) = 222
Since they are 7 in the family, then we'll divide the sum with 7
222 ÷ 7 = 31 5/7
Therefore the average age of the family is 31 5/7 yrs.
[tex]You'll \ get \ the \ sum \ of \ their \ ages \ and \ you'll \ get; \\ \\ 67(2)+35(2)+6(3) \\ \\ 134+70+18 \\ \\ The \ sum \ is \ equal \ to \ \boxed{222} \\ \\ Divide \ the \ sum \ by \ 7 \ since \ their \ are \ 7 \ family \ members. \\ \\ \frac{222}{7}=31 \frac{5}{7} \\ \\ Thus, \ the \ average \ age \ of \ the \ certain \ family \ is \ \boxed{31 \frac{5}{7}} [/tex]

Hope it Help:)
-----Domini-----