Question 1074128
Try to make some sense of this: g = girl's age; m = Mom's age; d = Dad's age
Write an equation for each statement
:
A girl is half years the age of her mother.
g = {{{1/2}}}m 
The dad is five years older than the mother.
d = m + 5
The total of their ages is 100
d + m + g = 100
we can replace d with (m+5) and g with {{{1/2}}}m
(m+5) + m + {{{1/2}}}m = 100
multiply by 2
2(m+5) + 2m + m = 200
2m + 10 + 2m + m = 200
5m = 200 - 10
5m = 190
m = 38 yrs is Mom's age
then
38+5 = 43 yrs is Dad's age
and
38/2 = 19 yrs is the girl's age
:
how old is the girl, the mother and the dad?