Question 231588: john is twice as old as his friend peter. peter is 5 years older than alice. in 5 years, john will be three times as old as alice. how old is peter now.
hello my name is toni and am a freshman in high schools, need some help with this problem, thank you.
Answer by stanbon(75887)   (Show Source):
You can put this solution on YOUR website! john is twice as old as his friend peter.
j=2p
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peter is 5 years older than alice.
a = a+5
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in 5 years, john will be three times as old as alice.
In 5 years john will be j+5
In 5 years alice will be a+5
Equation:
(j+5) = 3(a+5)
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how old is peter now.
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You have three Equations:
j = 2p
p = a+5
(j+5)= 3(a+5)
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Rearrange:
j = 2p
a = p-5
3a - j = -10
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Substitute into the 3rd equation to get:
3(p-5)- 2p = -10
3p-15 - 2p = -10
p - 15 = -10
p = 5 (peter's age now)
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Cheers,
Stan H.
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