SOLUTION: A man has four sons of different ages. Each of the older three sons is twice the age of the oldest of his younger brothers. The father's age is twice the age of his sons' ages. The
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Question 406295: A man has four sons of different ages. Each of the older three sons is twice the age of the oldest of his younger brothers. The father's age is twice the age of his sons' ages. The sum of the father's and sons' age is 45. What is the oldest sons' age? Stumped Thank You for any help
Answer by ankor@dixie-net.com(22740) (Show Source): You can put this solution on YOUR website!
A man has four sons of different ages.
Each of the older three sons is twice the age of the oldest of his younger brothers.
The father's age is twice the age of his sons' ages.
The sum of the father's and sons' age is 45.
What is the oldest sons' age?
:
let f = father's age
4 sons, a, b, c, d (a is oldest)
:
" Each of the older three sons is twice the age of the oldest of his younger brothers"
a = 2b
b = 2c
c = 2d
:
"The father's age is twice the age of his sons' ages."
Let s = the sum of the sons' ages
f = 2s
:
"The sum of the father's and sons' age is 45."
f + s = 45
f = 45 - s
replace f with 2s
2s = 45 - s
2s + s = 45
3s = 45
s =
s = 15 yrs is the sum of sons' ages
then
f = 2(15)
f = 30 yrs is father's age
:
" What is the oldest sons' age?"
a + b + c + d = 15
we know c = 2d, therefore
a + b + 2d + d = 15
we know b = 2c, therefore
a + 4d + 2d = d = 15
we know a = 2b, therefore
8d + 4d + 2d + d = 15
15d = 15
d = 1 yrs is d's age
and
a = 8(1) the oldest son is 8 yrs old
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