SOLUTION: the sum of the ages of peter and paul is 24. five years ago their respective ages were in the ratio 3:4. how old will they be in 3 years' time?
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Question 1171264: the sum of the ages of peter and paul is 24. five years ago their respective ages were in the ratio 3:4. how old will they be in 3 years' time? Found 2 solutions by ankor@dixie-net.com, greenestamps:Answer by ankor@dixie-net.com(22740) (Show Source):
You can put this solution on YOUR website! x = Peter's present age
y = Paul's
Write an equation for each statement
:
the sum of the ages of peter and paul is 24.
x + y = 24
five years ago their respective ages were in the ratio 3:4. =
cross multiply
4(x-5) = 3(y-5)
4x - 20 = 3y - 15
4x = 3y - 15 + 20
4x = 3y + 5
4x - 3y = 5
:
Use elimination with 1st equation, multiply it by 3
3x + 3y = 72
4x - 3y = 5
----------------addition eliminates y find x
7x = 77
x = 77/7
x = 11 years is Peter's age
and
11 + y = 24
y = 24- 11
y = 13 is Paul's age
:
how old will they be in 3 years' time?
Obviously, Peter will 14 and Paul will 16
:
:
Check their ages 5 yrs ago: =
