Step 1
Type A coffee costs $4.35 per pound
Type B coffee cost $5.45 per pound.
Manuel made 175 pounds of the blend at a total cost of $866.85
Required; To find how many pounds of type A coffee used.
Step 2
Write a system of equation
[tex]\begin{gathered} 4.35A+5.45B=866.85--(1) \\ A+B=175---(2) \end{gathered}[/tex]Step 3
Find the value of A
[tex]\begin{gathered} \text{From 2} \\ B=175-A \\ \text{Substituting this in 1 gives} \\ 4.35A+5.45(175-A)=866.85 \\ 4.35A+953.75-5.45A=866.85 \\ 953.75-866.85=5.45A-4.35A \\ 86.9=1.1A \\ \frac{1.1A}{1.1}=\frac{86.9}{1.1} \\ A=79\text{ pounds} \end{gathered}[/tex]Hence, Manuel used 79 pounds of type A coffee