Question 322312
"Twelve years ago Jack was five times as old as Jill. In three years time Jill will be half of Jack's age. What are Jack and Jill's present ages?"
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let Jill's age be x now
Let Jack's age be y now
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12 years ago their ages were
Jill x-12
Jack y-12
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y-12=5(x-12)
y-12=5x-60
y-5x=-48.......... equation 1
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after 3 years their ages will be
Jill x+3
Jack y+3
(x+3)= 1/2 (y+3)
2(x+3)=y+3
2x+6=y+3
2x-y=-3......... equation 2
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Add equation 1&2

y-5x+2x-y=-48-3
-3x=-51
x= 17 which is Jill's age now
Plug the value of x in equation1
y-85=-48
y=37 Jack's age now