Question: Ages of Ebo and Atu

Comment on Ages of Ebo and Atu

Can you add how to do this with one variable? I've been trying and keep getting stumped!
greenlight-admin's picture

Sure thing.
Let A = Atu's age 5 YEARS AGO.
This means 3A = Ebo's age 5 YEARS AGO.

That was 5 YEARS AGO. To find their ages 3 YEARS FROM NOW, we must add 8 years to the above ages.
So, A + 8 = Atu's age 3 YEARS FROM NOW
And 3A + 8 = Ebo's age 3 YEARS FROM NOW

We're told that, 3 YEARS FROM NOW, Abo's age will be TWICE that of Atu's age
In other words, 3A + 8 = 2(A + 8)
Expand: 3A + 8 = 2A + 16
Solve to get: A = 8
This means that Atu was 8 years old 5 YEARS AGO.
And it means EBO was 24 years old 5 YEARS AGO.

So, their CURRENT AGES are: Atu - 13 years old and Ebo - 29 years old
The SUM of their CURRENT ages = 13 + 29 = 42

Is there a way to solve this with two variable substitution?

E = 3A + 10
E = 2A + 3
------using the 2nd equation------
E = 2A + 3
E - 3 = 2A
A = E/2 - 3/2 (Substitute this into the first equation)

I get E = 11
greenlight-admin's picture

Be careful. You made a mistake when took the equation 3A - E = 10 rewrote it as E = 3A + 10.

Take: 3A - E = 10
Add E to both sides: 3A = E + 10
Subtract 10 from both sides: 3A - 10 = E (you have E = 3A + 10)

Cheers,
Brent

I have trouble when I work with this kind of problems. In the table I included the relationship between one age to another one. Is my mistake.. Could you please share another link to work with similar problems. Thanks so much.
greenlight-admin's picture

There are some extra practice questions in the Reinforcement Activities box here: https://www.greenlighttestprep.com/module/gre-word-problems/video/909

Thanks.

sir could you share some pratice problems for age ques.
greenlight-admin's picture

Check out the linked practice questions in the Reinforcement Activities box here: https://www.greenlighttestprep.com/module/gre-word-problems/video/909

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