SOLUTION: Paul is Twice as old as his friend Peter. Peter is 5 years older than Mary. In 5 years, Paul will be three times as old as Mary. How old is Peter now

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Question 1008918: Paul is Twice as old as his friend Peter. Peter is 5 years older than Mary. In 5 years, Paul will be three times as old as Mary. How old is Peter now

Answer by ankor@dixie-net.com(22740) About Me  (Show Source):
You can put this solution on YOUR website!
let a = Paul's age
let p = Peter's age
let m = Mary's
:
Write an equation for each statement
:
Paul is Twice as old as his friend Peter.
a = 2p
:
Peter is 5 years older than Mary.
p = m + 5
or
m = p - 5
:
In 5 years, Paul will be three times as old as Mary.
a + 5 = 3(m+5)
a + 5 = 3m + 15
a = 3m + 15 - 5
a = 3m + 10
:
How old is Peter now
In the above equation, replace a with 2p, replace m with (p-5)
2p = 3(p-5) + 10
2p = 3p - 15 + 10
2p - 3p = -5
-p = -5
p = 5 yrs is Peter's age now
:
:
This does not seem right because then Mary's age is 0, Paul is 10