.
J = R - 3 (1) ("Janet is three years younger than Rebecca.".)
J-8 = 0.5*(R-8) (2) ("8 years ago . . . ")
Substitute eq(1) into eq(2). You will get
(R-3) - 8 = 0.5*(R-8)
R-11 = 0.5*(R-8)
Multiply it by 2 (both sides)
2R - 22 = R - 8
2R - R = 22 - 8 = 14 ====> R = 14.
Answer. Rebecca is 14 years old. Janet is R-3 = 14-3 = 11 years old.
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On age word problems, see the lessons
- 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
- Age problems for mental solution
in this site.
Read them and become an expert in solving age problems.
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- ALGEBRA-I - YOUR ONLINE TEXTBOOK.
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