GreenlightTestPrep wrote:

Presently, Fred is 4 times as old as Gary. In 10 years, Fred will be 3 times as old as Gary. How old (in years) will Fred be in 3 years?

Let's solve the question using 2 variables

Let F = Fred's PRESENT age

Let G = Gary's PRESENT age

Presently, Fred is 4 times as old as GaryIn other words,

F = 4GIn 10 years, Fred will be 3 times as old as Gary.IN 10 YEARS, Fred's age = F + 10

IN 10 YEARS, Gary's age = G + 10

If Fred will be 3 times as old as Gary, we can write: F + 10 = 3(G + 10)

Expand: F + 10 = 3G + 30

Rearrange to get:

F = 3G + 20We now have the following system:

F = 4GF = 3G + 20Since both equations set equal to F, we can write: 4G = 3G + 20

When we solve this, we get G = 20

Since

F = 4G, we can now say that F = 4(20) = 80

In other words, Fred's PRESENT age is 80

So, IN 3 YEARS, Fred's age will be 83

Answer: 83

Cheers,

Brent

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Brent Hanneson – Creator of greenlighttestprep.com

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