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Question
John is twice as old as his son. In 42 years, the ratio of their ages will be 4:3. What is
the son’s current age?
Let x = the son's age so that the father's age is 2x. In 42 years the father's age will be 2x + 42 and the son's age will be x + 42
[2x + 42]/[x + 42] = 4/3 -> 3[2x + 42] = 4[x + 42] -> 6x + 126 = 4x + 168 -> 2x = 42 -> x = 21
(the son's current age) and 2(21) = 42 the father's current age. So in 43 years the father will be 84 and the son will be 63 which is in a ratio of 4/3.
Math Prof
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Advanced Math
Answers by Expert:
Sherry Wallin
Expertise
I can answer most questions up through Calculus and some in Number Theory and Abstract Algebra.
Experience
I have had my Bachelor's Degree since 1987 and have been a teacher since 1988. I earned my Masters Degree in Mathematics May 2010. I have been teaching at the same community college since 2002.
Education/Credentials
I have taught 12 years at the community college level, medical college, and technical college as well as a high school instructor and alternative education instructor and charter school instructor.
Awards and Honors
Master's GPA 3.56
Bachelor's GPA 3.34
Post grad work not degree related GPA 4.0
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