Question

3/7 of the people who live in the apartment building are men. 5/8 of the remaining people are women. The rest are children. a total of 275 men and women live in the building. How man people live in the apartment building altogether?

Answer 1

Explanation:

people in building ---- x

children --- y

men + women + children = x

(3/7)x + (5/8)(4/7)x + y = x

3x/7 + 5x/14 + y = x

times 14

6x + 5x + 14y = 14x

14y = 3x

y + 220 =x

sub into the other one

14y = 3(y+220)

11y = 660

y = 60

then 14(60) = 3x ---> x = 280

So we have 280 people in the building.

check: 3/7 of 280 are men = 120

leaving 160 women and children

5/8 of these ot 100 are women

so we have 120 men, 100 women and 60 children!