Question 752624
The ratio of sam's age to his father's is 1:3.
 In five years, Sam's age will be 3/7 of his father's age.
 What is the age difference of Sam and his father?
:
Let x = the multiplier
then
1x = age of sam
and
3x = age of father
:
"In five years, Sam's age will be 3/7 of his father's age."
{{{((x+5))/((3x+5))}}} = {{{3/7}}}
Cross multiply
3(3x+5) = 7(x+5)
9x + 15 = 7x + 35
9x - 7x = 35 - 15
2x = 20
x = 20/2
x = 10 is the multiplier
then
3(10) = 30 yrs is Dad's age
1(10) = 10 yrs is Sam's age
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Age dif: 20 yrs