Question 333436
A mother is 8 times as old as her daughter and 4 times as old as her son.
m = 8d
m = 4s
:
How old is each if the son is 4 years older than the daughter?
s = d + 4
:
replace s with (d+4) in the equation m = 4s
m = 4(d+4)
m = 4d + 16
Replace m with 8d from the 1st equation
8d = 4d + 16
8d - 4d = 16
4d = 16
d = 4 yrs is the daughter's age
:
We know that s = d+4, therefore
s = 4 + 4
s = 8 yrs son's age
then 
m = 4s
m = 4(8)
m = 32 yrs is Mom's age
:
;
summarize; Mom is 32, son is 8, daughter is 4