You can put this solution on YOUR website! let f = F's present age
Let c = C's present age
:
Write an equation for each statement, then simplify it:
:
five years ago, felipe was half of carolinas age.
f - 5 = .5(c - 5)
f - 5 = 5c - 2.5
f = .5c - 2.5 + 5
f = .5c + 2.5
:
at that time, the sum of their ages was 30.
(f-5) + (c-5) = 30
f + c - 10 = 30
f + c = 30 + 10
f + c = 40
:
Replace f with (.5c+2.5) from the 1st equation
(.5c+2.5) + c = 40
1.5c = 40 - 2.5
1.5c = 37.5
c =
c = 25 yrs is C's present age
:
How old is felipe now?
Find f using the equation: f + c = 40
f + 25 = 40
f = 40 - 25
f = 15 yrs is F's present age
:
:
Check solutions using the statement:
five years ago, felipe was half of carolinas age.
15 - 5 = .5(25 - 5)
10 = .5(20); confirms our solutions
