You can put this solution on YOUR website! ): Crisner is 3 years older than her niece Josephine.
In 7 years she will be six seventh of her age.
How old are they?
:
Let c = C's age now
Let j = J's age
;
Write an equation for each statement
:
"): Crisner is 3 years older than her niece Josephine."
c = j + 3
:
"In 7 years she will be six seventh of her age."
j + 7 = (c+7)
Get rid of that annoying fraction, mult both sides by 7
7(j+7) = 6(c+7)
7j + 49 = 6c + 42
7j = 6c + 42 - 49
7j = 6c - 7
replace c with (j+3) from the 1st statement
7j = 6(j+3) - 7
7j = 6j + 18 - 7
7j - 6j = 11
j = 11 yrs is J's age
then
11 + 3 = 14 yrs is C's age
;
;
see if that works
j + 7 = (c+7)
11 + 7 = (14+7)
18 = (21)
7 cancels into 21
18 = 6(3)
