Question

A hair salon receives a shipment of 84 bottles of hair conditioner to use and sell to customers. The two types are labels type A & type B. A costs $6.50 per bottle and B costs $8.25 per bottle. The hair salon's invoice is $588. How many of each type of conditioner are in the shipment?

Answer 1

$x-\ botlle\ A\\y-\ bottle\ B\\\\ \left \{ {{x+y=84} \atop {6,5x+8,25y=588}} \right. \\\\ \left \{ {{x=84-y} \atop {6,5x+8,25y=588}} \right. \\\\Substitution\ method\\\\ 6,5(84-y)+8,25y=588\\\\ 546-6,5y+8,25y=588\ \ \ | subtract\ 546 1,75y=42\ \ \| divide\ by\ 1,75\\\\y=24\\\\There\ were\ 24\ bottles\ B\ and\ 42\ bottle\ A.$