Fourty liters of a 40% acid solution is obtained by mixing a 28% solution with a 50% solution.Write a system of equations in which one equation represents the amount of final mixture required and the other represents the percent of acid in the final mixture.Let x and y represent the amounts of the 28% and 50% solutions, respectively.
A) $\left\{ \begin{array} { l }
x + y = 40 \
0.28 x + 0.5 y = 40
\end{array} \right.$
B) $\left\{ \begin{array} { l }
0.28 x + 0.5 y = 40 \
x + y = 16
\end{array} \right.$
C) $\left\{ \begin{array} { l }
x + y = 40 \
0.28 x + 0.5 y = 16
\end{array} \right.$.
D) $\left\{ \begin{array} { l }
x + y = 40 \
0.28 x + 0.5 y = 16
\end{array} \right.$
E) $\left\{ \begin{array} { l }
0.28 x + 0.5 y = 40 \
x + y = 16
\end{array} \right.$.

Question

Fourty liters of a 40% acid solution is obtained by mixing a 28% solution with a 50% solution.Write a system of equations in which one equation represents the amount of final mixture required and the other represents the percent of acid in the final mixture.Let x and y represent the amounts of the 28% and 50% solutions, respectively.  
A)  $\left\{ \begin{array} { l } 
x + y = 40 \
0.28 x + 0.5 y = 40
\end{array} \right.$
B)  $\left\{ \begin{array} { l } 
0.28 x + 0.5 y = 40 \
x + y = 16
\end{array} \right.$
C) $\left\{ \begin{array} { l } 
x + y = 40 \
0.28 x + 0.5 y = 16
\end{array} \right.$.
D)  $\left\{ \begin{array} { l } 
x + y = 40 \
0.28 x + 0.5 y = 16
\end{array} \right.$
E)  $\left\{ \begin{array} { l } 
0.28 x + 0.5 y = 40 \
x + y = 16
\end{array} \right.$.

Quizplus · Accepted Answer

The first equation $x + y = 40$ represents the total volume of the mixture. The second equation $0.28x + 0.5y = 16$ represents the total amount of acid in the final 40% solution (40% of 40 liters is 16 liters of acid).

Fourty Liters of a 40% Acid Solution Is Obtained by Mixing