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13. Nick is five years older than Will. The sum of their ages is 21. How old is Nick? Solve algebraically.

User Isick
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1 Answer

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Answer:

Nick = 13 years old.

Explanation:

Define the variables:

  • Let n = the age of Nick (in years).
  • Let w = the age of Will (in years).

Given:

  • Nick is 5 years older than Will.
  • The sum of their ages is 21.

Create a system of equations with the given information and defined variables:


\begin{cases} w=n-5\\n+w=21\end{cases}

Substitute the first equation into the second equation and solve for n:


\implies n+(n-5)=21


\implies 2n-5=21


\implies 2n-5+5=21+5


\implies 2n=26


\implies 2n / 2=26 / 2


\implies n=13

Therefore, Nick is 13 years old.

To find the age of Will, simply substitute the found value of n into the first equation and solve for w:


\implies w=13-5


\implies w=8

Therefore, Will is 8 years old.

User Barmaley
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