SOLUTION: A says to B,"I am 5 times as old as you were when i was as old as you are".If the sum of their present ages of A & B=64. What are their present ages

Algebra ->  Coordinate Systems and Linear Equations  -> Linear Equations and Systems Word Problems -> SOLUTION: A says to B,"I am 5 times as old as you were when i was as old as you are".If the sum of their present ages of A & B=64. What are their present ages      Log On


   



Question 713537: A says to B,"I am 5 times as old as you were when i was as old as you are".If the sum of their present ages of A & B=64. What are their present ages
Answer by josmiceli(19441) About Me  (Show Source):
You can put this solution on YOUR website!
Let +a+ = A's age now
Let +b+ = B's age now
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" when I was as old as you are "
That means when A's age was equal to +b+
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" as old as you were "
The difference in their ages is always +a-b+
so, at that time, B was +b+-%28+a-b+%29+=+2b+-+a+
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" A says to B,"I am 5 times "
A's present age, which is +a+ is +5%2A%28+2b+-+a+%29+
so I can say
(1) +a+=+5%2A%28+2b-a+%29+
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" the sum of their present ages of A & B = 64 "
(2) +a+%2B+b+=+64+
(2) +a+=+64+-+b+
and
(1) +a+=+5%2A%28+2b-a+%29+
(1) +a+=+10b+-+5a+
(1) +6a+=+10b+
(1) +a+=+%285%2F3%29%2Ab+
By substitution:
(1) +64+-+b+=+%285%2F3%29%2Ab+
(1) +%288%2F3%29%2Ab+=+64+
(1) +b+=+%283%2F8%29%2A64+
(1) +b+=+24+
and, since
(2) +a+=+64+-+b+
(2) +a+=+64+-+24+
(2) +a+=+40+
A is 40 and B is 24
check:
" when I was as old as you are "
When A was 24, B had to be +24+-%28+40+-+24+%29+=+24+-+16+
+24+-+16+=+8+
"I am 5 times as old as you were"
A is +5%2A8+=+40+
OK