SOLUTION: Dear Tutor, I am having a hard time trying to work out this problem. Would you please be so kind as to try and help me. This is the question: John is 3 times younger than h

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Question 522747: Dear Tutor,
I am having a hard time trying to work out this problem. Would you please be so kind as to try and help me.
This is the question:
John is 3 times younger than his dad's age. The sum of their ages is 79. Find Johns age as a fraction.
I tied by saying 79 divide by 3 and got 26 and a third but I would like to know for sure.
Thank you for taking the time to help me
kind regards
Tracey
Answer by ankor@dixie-net.com(22740) About Me  (Show Source):
You can put this solution on YOUR website!
I would do it this way
:
John is 3 times younger than his dad's age.
d = 3j
but they want John's age as a fraction, divide both sides by 3
j = 1%2F3d
:
The sum of their ages is 79.
d + j = 79
:
replace j with 1%2F3d
1d + 1%2F3d = 79
:
1 1/3 = 4/3, so write it
4%2F3d = 79
:
multiply both sides by 3, to get rid of the denominators
4d = 3(79)
4d = 237
d = 237/4
d = 59.25 is Dad's age
then
j = 1%2F359.25
j = 19.75 or 193%2F4 yr is John's age
:
:
Check this by finding the sum of their ages
59.25
19.75
-----
79.00