SOLUTION: A man is 3 times as old as his son. Four years ago, the sum of their age as 60 years. How old is the son

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Question 1067921: A man is 3 times as old as his son. Four years ago, the sum of their age as 60 years. How old is the son
Answer by ikleyn(52810)   (Show Source): You can put this solution on YOUR website!
.
M = 3S,                (1)   ("A man is 3 times as old as his son")
(M-4) + (S-4) = 60.    (2)   ("Four years ago . . . ")


--->  substitute (1) into (2), simplify and solve for S, the son's age.


3S- 4 + S - 4 = 60,

4S - 8 = 60  --->  4S = 68  --->  S =  = 17.


Answer.  The son is 17. The man is 51 years old now.

There is a bunch of lessons on age word problems
    - Age problems and their solutions
    - A fresh formulation of a traditional age problem
    - Really intricate age word problem
    - Selected age word problems from the archive
    - OVERVIEW of lessons on age problems
in this site.

Read them and become an expert in solving age problems.

Also, you have this free of charge online textbook in ALGEBRA-I in this site
    - ALGEBRA-I - YOUR ONLINE TEXTBOOK.

The referred lessons are the part of this online textbook under the topic "Age word problems".


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