Question 664952: In four years time Angela will be twice as old as Barry and four times as old as Carol. Three years ago Angela was three times as old as Barry. How old are Angela, Barry and Carol now?
Answer by ankor@dixie-net.com(22740)   (Show Source):
You can put this solution on YOUR website! In four years time Angela will be twice as old as Barry and four times as old as Carol.
a + 4 = 2(b+4)
a + 4 = 2b + 8
a = 2b + 8 - 4
a = 2b + 4
and
a + 4 = 4(c+4)
a + 4 = 4c + 16
a = 4c + 16 - 4
a = 4c + 12
:
Three years ago Angela was three times as old as Barry.
a - 3 = 3(b-3)
a - 3 = 3b - 9
a = 3b - 9 + 3
a = 3b - 6
:
a = a, so we can write an equation
3b - 6 = 2b + 4
3b - 2b = 4 + 6
b = 10 yrs old
:
Find a
a = 3(10) - 6
a = 24 yrs old
:
Find c
4c + 12 = a
4c + 12 = 24
4c = 24 - 12
4c = 12
c = 3 yrs old
:
How old are Angela, Barry and Carol now? 24, 10, 3
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