SOLUTION: Steve is three times as old as Theresa. In four years he willl be twice as old as she will be. How old is each now?

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Question 196867This question is from textbook
: Steve is three times as old as Theresa. In four years he willl be twice as old as she will be. How old is each now? This question is from textbook

Answer by ankor@dixie-net.com(22740) About Me  (Show Source):
You can put this solution on YOUR website!
Steve is three times as old as Theresa. In four years he will be twice as old as she will be. How old is each now?
:
Let s = Steve's age now
Let t = Teresa's age now
:
Write an equation for each statement:
"Steve is three times as old as Teresa."
s = 3t
:
"In four years he will be twice as old as she will be."
s + 4 = 2(t+4)
s + 4 = 2t + 8
s = 2t + 8 - 4
s = 2t + 4
Substitute 3t for s and find t
3t = 2t + 4
3t - 2t = 4
t = 4 yrs is Teresa's age
then
s = 3(4)
s = 12 yrs is Steve's age
:
Check solution in the statement
"In four years he will be twice as old as she will be."
12 + 4 = 2(4 +4)