Question 943784: Rowena's age is three more than twice Mary's age. three years ago, Rowena was four times as old as mary was then. How old are they now?
Answer by ankor@dixie-net.com(22740) (Show Source):
You can put this solution on YOUR website! Rowena's age is three more than twice Mary's age.
three years ago, Rowena was four times as old as mary was then.
How old are they now?
:
Let r = R's age
let m = M's age
:
WRite an equation for each statement.
:
"Rowena's age is three more than twice Mary's age."
r = 2m + 3
" three years ago, Rowena was four times as old as mary was then."
r - 3 = 4(m-3)
r - 3 = 4m - 12
r = 4m - 12 + 3
r = 4m - 9
Replace r with (2m+3), from the 1st statement
2m + 3 = 4m - 9
3 + 9 = 4m - 2m
12 = 2m
m = 12/2
m = 6
Mary is 6 yrs old
then
r = 2m + 3
r = 2(6) + 3
r = 15 yrs is Rowena's age
:
;
See if that checks out in the statement:
" three years ago, Rowena was four times as old as mary was then. "
15 - 3 = 4(6 - 3)
12 = 4(3)
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