SOLUTION: My family consists of father, mother and a sister. My father is 2 years older than my mother. My sister's age is 3 less than 1/2 the age of my mother. The sum of 1/3 of my father's
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-> SOLUTION: My family consists of father, mother and a sister. My father is 2 years older than my mother. My sister's age is 3 less than 1/2 the age of my mother. The sum of 1/3 of my father's
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Question 910263: My family consists of father, mother and a sister. My father is 2 years older than my mother. My sister's age is 3 less than 1/2 the age of my mother. The sum of 1/3 of my father's age and 1 more than the half the age of my sister is my age. If the total of all our ages is now 141, how old am I? Answer by ankor@dixie-net.com(22740) (Show Source):
You can put this solution on YOUR website! let y = your age
let f = father's age
let m = mother's age
let s = sister's age
:
Write an equation for each statement;
:
My father is 2 years older than my mother.
f = m + 2
My sister's age is 3 less than 1/2 the age of my mother.
s = m - 3
The sum of 1/3 of my father's age and 1 more than the half the age of my sister is my age.
y = f + s + 1
replace f with (m+2), replace s with (.5m-3)
y = (m+2) + (.5m-3) + 1
:
If the total of all our ages is now 141,
y + f + m + s = 141
:
replace f with (m+2); replace s with (.5m-3)
y + (m+2) + m + (.5m-3) = 141
y + 2.5m - 1 = 141
y + 2.5m = 142
:
replace y (m+2) + (.5m-3) +1 + 2.5m = 142
:
multiply equation by 6
2(m+2) + 3(.5m-3) + 6(2.5m) + 6 = 6(142)
2m + 4 + 1.5m - 9 + 15m + 6 = 852
18.5m + 1 = 852
18.5m = 851
m = 851/18.5
m = 46 yrs is Mom's age
then
48 yrs is Dad's age
and
.5(46) - 3 = 20 yrs is sisters age
how old am I?
y = (48) + (20) + 1
y = 16 + 10 + 1
y = 27 yrs is your age
:
:
See if that adds up
27 + 48 + 46 + 20 = 141
