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Please help me with this sample question.The sample questions only allow me to test each country once before moving to the next. I need all countries.

Please help me with this sample question.The sample questions only allow me to test-example-1
User Roubachof
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2 Answers

5 votes
The first one is 76
The second one is 25
The third one is 18
User Chaitanya MSV
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7 votes

Let be "a" the number of medals that Country A won, "b" the number of medals that Country B won, and "c" the number of medals that Country C won.

You can set up the following System of equations using the information given in the exercise:


\begin{cases}a+b+c=119 \\ b=c+7 \\ a=b+c+33\end{cases}

In order to solve the System of equations, you can follow these steps:

1. Substitute the second equation into the third equation:


\begin{gathered} a=b+c+33 \\ a=(c+7)+c+33 \\ a=2c+40 \end{gathered}

2. Substitute this new equation and the second original equation, into the first original equation:


(2c+40)+(c+7)+c=119

3. Solve for "c":


\begin{gathered} 4c+47=119 \\ 4c=119-47 \\ \\ c=(72)/(4) \\ \\ c=18 \end{gathered}

4. Knowing the value of "c", you can substitute it into the second original equation and then evaluate, in order to find the value of "b":


\begin{gathered} b=(18)+7 \\ b=25 \end{gathered}

5. Knowing the value of "b" and "c", you can substitute them into the third original equation and then evaluate, in order to find the value of "a":


\begin{gathered} a=b+c+33 \\ a=(25)+(18)+33 \\ a=76 \end{gathered}

Therefore, the answer is:

- Country A won 76 medals.

- Country B won 25 medals.

- Country C won 18 medals.

User Mrjmh
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