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A chemical company makes two brands of antifreeze. The first brand is 70% pure antifreeze, and the second brand is 95% pure antifreeze. In order to obtain130 gallons of a mixture that contains 85% pure antifreeze, how many gallons of each brand of antifreeze must be used?First brand:Second brand:Solve by percent mixture using system of linear equations.

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Given:

A chemical company makes two brands of antifreeze.

The first brand is 70% pure antifreeze.

The second brand is 95% pure antifreeze.

We need to make 130 gallons of a mixture that contains 85% pure antifreeze.

Let we will use (x) gallons from the first brand

So, we will use (130 - x) from the second brand.

The mixture must contain 85% pure antifreeze.

So, we can write the following equation:


70x+95(130-x)=85*130

Solve the equation to find (x):


\begin{gathered} 70x+95*130-95x=85*130 \\ -25x+12350=11050 \\ -25x=11050-12350 \\ -25x=-1300 \\ x=(-1300)/(-25)=52 \end{gathered}

So, the answer will be:

First brand: 52 gallons

Second brand: 78 gallons

User Marco Torchiano
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