SOLUTION: John is 5 years older than bob. Three years ago he was twice as bob. How old is john?

Question 749797: John is 5 years older than bob. Three years ago he was twice as bob. How old is john?
Answer by ankor@dixie-net.com(22740) (Show Source): You can put this solution on YOUR website!
John is 5 years older than bob.
j = b+5
:
Three years ago he was twice as bob.
j-3 = 2(b-3)
j - 3 = 2b - 6
j = 2b - 6 + 3
j = 2b - 3
replace j with (b+5)
b + 5 = 2b - 3
5 + 3 = 2b - b
b = 8 yr is Bob's age
:
How old is john?
j = 8 +5
j = 13
:
:
Check solutions in the statement:
"Three years ago he was twice as bob."
13 - 3 = 2(8-3); confirms our answer
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