SOLUTION: Boy is twice old as girl. If boy was two and half times as old as girl Was six years ago what's their present age

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Question 1069764: Boy is twice old as girl. If boy was two and half times as old as girl
Was six years ago what's their present age

Answer by josmiceli(19441) About Me  (Show Source):
You can put this solution on YOUR website!
Let +a+ = boy's age now
Let +b+ = girl's age now
---------------------------
(1) +a+=+2b+
(2) +a+-+6+=+2.5%2A%28+b+-+6+%29+
---------------------------
(2) +a+-+6+=+2.5b+-+15+
(2) +a+=+2.5b+-+9+
Substitute (1) into (2)
(2) +2b+=+2.5b+-+9+
(2) +.5b+=+9+
(2) +b+=+18+
and
(1) +a+=+2b+
(1) +a+=+2%2A18+
(1) +a+=+36+
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The boy is 36
The girl is 18
-------------------
(2) +a+-+6+=+2.5%2A%28+b+-+6+%29+
(2) +36+-+6+=+2.5%2A%28+18+-+6+%29+
(2) +30+=+2.5%2A12+
(2) +30+=+30+
OK
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I might have misread this. 36 yrs old
is not a boy. Get another opinion
on this.