Question 120555: Last year Sue was three times as old as Pablo. Next year she will be twice as old as Pablo is. How old is each now?
I don't understand this at all.): Could someone please help me?
Answer by ankor@dixie-net.com(22740)   (Show Source):
You can put this solution on YOUR website! Last year Sue was three times as old as Pablo. Next year she will be twice as old as Pablo is. How old is each now?
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This is not hard
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Let s = Sue's age now, Let p = Pab's age now
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Last year their ages would be:
(s-1) and (p-1), right?
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It said,"Last year Sue was three times as old as Pablo." so we can say:
(s-1) = 3(p-1)
s - 1 = 3p - 3; just do some basic algebra on it
s = 3p - 3 + 1
s = (3p - 2)
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Next year she will be twice as old as Pablo is. How old is each now?
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Next year their ages would be:
(s+1) and (p+1), right?
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It says,"Next year she will be twice as old as Pablo is." so we can say:
(s+1) = 2(p+1)
s + 1 = 2p + 2
s = 2p + 2 - 1
s = 2p + 1
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How old is each now?:
Using the 1st equation we found s = (3p-2), substitute that for s in the 2nd eq
3p - 2 = 2p + 1
3p = 2p + 1 + 2
3p - 2p = 3
p = 3 yrs is Pab's present age
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Find Sue's age using s = 2p + 1
s = 2(3) + 1
s = 6 + 1
s = 7 yrs is Sue's present age
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Check out our solutions by using the two sentences:
Last year Sue was three times as old as Pablo.
(7-1) = 3(3-1) true
and
Next year she will be twice as old as Pablo is.
(7 + 1) = 2(3+1) also true
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A lot of steps, but each step is logical and simple, did you understand this?
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