Question 410519
Let r = Irene's age
Let m = Michele's age
:
Write an equation for each statement:
:
Irene's present age is 1/2 of Michele's present age.
r = {{{1/2}}}m
we can also write it as
m = 2r
:
 In 12 years, Irene's age will be 5/8 of Michele's age.
r + 12 = {{{5/8}}}(m + 12)
:
Multiply both sides by 8, results
8(r + 12) = 5(m + 12)
8r + 96 = 5m + 60
8r = 5m + 60 - 96
8r = 5m - 36
replace m with 2r
8r = 5(2r) - 36
8r = 10r - 36
36 = 10r - 8r
36 = 2r
 r = {{{36/2}}}
r = 18 yrs is Irene's present age
then
m = 2(18)
m = 36 is Michele's age
;
:
Check that in the statement:
"In 12 years, Irene's age will be 5/8 of Michele's age.
18 + 12 = {{{5/8}}}(36 + 12
30 = {{{5/8}}}(48); confirms our solutions