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Ahmir is 20 years older than Brynn. In 5 years Ahmir will be 3 times as old as Brynn. what are their current ages? A. Ahmir is 20, Brynn is 5B. Ahmir is 60, Brynn is 40C. Ahmir is 25, Brynn is 5D. Ahmir is 5, Brynn is 25

User Sybind
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1 Answer

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Let x be Ahmir age and let y be Brynn age.

We know that Ahmir is 20 years older than Brynn that means that:


x=y+20

Now, we know that in 5 years Ahmir will be 3 times as old as Brynn, this means that:


\begin{gathered} x+5=3(y+5) \\ x+5=3y+15 \\ x-3y=10 \end{gathered}

Then we have the following system of equations:


\begin{gathered} x-y=20 \\ x-3y=10 \end{gathered}

Substracting the second equation from the first we have:


\begin{gathered} x-y-x+3y=20-10 \\ 2y=10 \\ y=(10)/(2) \\ y=5 \end{gathered}

Once we know the value for y we can know the value for x:


x=20+5=25

Therefore Ahmir is 25 and Brynn is 5; and the answer is C.

User Breathe
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