Age problem

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Age problem

by beater » Thu Jan 15, 2009 12:57 pm
This year, the sum of ages of the Perkins family members is 78. Currently, there are 4 members: husband, wife, daughter, and son. The husband is 4 years older than the wife. The daughter is two years older than the son. If the husband is 7 times older than the son, How old is the daughter?


a) 5
b) 7
c) 10
d) 13
e) 14
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by truplayer256 » Thu Jan 15, 2009 1:04 pm
I put everything in terms of D and solved for D.

That comes out to:

Husband: 7D-14
Wife: 7D-18
Son: D-2
Daughter: D

7D-14+7D-18+D-2+D=78
16D-34=78
D=7

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by dmateer25 » Thu Jan 15, 2009 1:10 pm
Son = x
Husband =7x
Daughter = x+2
Wife = 7x-4

x+7x+x+2+7x-4 = 16x – 2 = 78

16x = 80
x = 5

daughter = 5 + 2 = 7