Algebra/Math

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Question
A man is 24 years older than his son. 12 years ago, he was five times as old as his son. What are the present ages of both?

Answer
A man is 24.
Call the father's current age x and the son's current age y.

He is 24 years older, so x = y + 24.

The part on 12 years ago says that x - 12 = 5(y - 12).

Putting in the equation for x gives y + 24 - 12 = 5(y-12).
Simplifying the left and multiplying out the right gives y + 12 = 5y - 60.
Adding -5y - 12 to both sides gives -4y = -72.
Dividing by -4 gives y = 18.

Since x = y + 24, and y = 18, this means x = 42.

Checking out the age 12 years ago means the father was 42-12 = 30
and the son was 18-12=6.  Note that 30 = 5*6, so that's the correct answer.  

Algebra

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Scott A Wilson

Expertise

Any algebraic question you've got. That includes question that are linear, quadratic, exponential, etc.

Experience

I have solved story problems, linear equations, parabolic equations. I have also solved some 3rd order equations and equations with multiple variables.

Publications
Documents at Boeing in assistance on the manufacturiing floor.

Education/Credentials
MS at math OSU in mathematics at OSU, 1986. BS at OSU in mathematical sciences (math, statistics, computer science), 1984.

Awards and Honors
Both my BS and MS degrees were given with honors.

Past/Present Clients
Students in a wide variety of areas since the 80's; over 1,000 of them have been in algebra.

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