.
Five years from now, Jabin's grandmother will be 3 times as old as Jabin.
The sum of the squares of their ages in 5 years is 8410. what is Jabin's present age?
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This problem has a simple and elegant solution. All you need is to look
at the problem from the right point of view . . .
Let x be the Jabin's age in 5 years from now.
Then the grandmother's age in 5 years from now will be 3x, according to the condition.
Now we write equation for x as we read the problem
x^2 + (3x)^2 = 8410.
Simplify and find x
x^2 + 9x^2 = 8410
10x^2 = 8410
x^2 = 841
x = = 29 is the Jabin's age in 5 years from now.
ANSWER. This year, Jabin is 29-5 = 24 years old.
Solved.
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There is a bunch of lessons on age word problems
- Age problems and their solutions
- HOW TO algebreze and to solve age problems?
- 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
- Age problem for three participants
- 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".
Save the link to this online textbook together with its description
Free of charge online textbook in ALGEBRA-I
https://www.algebra.com/algebra/homework/quadratic/lessons/ALGEBRA-I-YOUR-ONLINE-TEXTBOOK.lesson
to your archive and use it when it is needed.