SOLUTION: my mum was 27 when i was born, 8 years ago she was twice as old as i shall be in 5 years time..how old am i now?

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Question 615867: my mum was 27 when i was born, 8 years ago she was twice as old as i shall be in 5 years time..how old am i now?
Found 2 solutions by scott8148, dragonwalker:
Answer by scott8148(6628) About Me  (Show Source):
You can put this solution on YOUR website!
m = i + 27

m - 8 = 2(i + 5)

substituting ___ (i + 27) - 8 = 2i + 10 ___ i + 19 = 2i + 10

Answer by dragonwalker(73) About Me  (Show Source):
You can put this solution on YOUR website!
Okay, so we need to represent your age as an unknown. Let us say x.
Five years from now you are going to be x + 5
Eight years ago your mum was twice this i.e. 2(x+5) or 2x+10
It also gives a clue at how old your mum was 8 years ago in another way:
She was 27 + your age at the time and you would have been x-8. So this means she was:
27+x-8
As both formulas represent her age 8 years ago they are equal to each other so:
2x+10 = 27+x-8
Solve for x:
2x-x = 27-8-10
x=9
so you would be 9 years old.