.
x = daughter
7x = mother
In three years
daughter = (x+3)
mother = 7x + 3
Equation
7x + 3 = 4*(x+3).
Solution
7x + 3 = 4x + 12
7x - 4x = 12 -3
3x = 9
x = 9/3 = 3.
ANSWER. Daughter is 3 years old. Mother is 7*3 = 21 years old.
Solved.
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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 problems
- Selected age word problems from the archive
- Age problems for mental solution
- Miscellaneous 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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