Bunuel wrote:

Richard's Roto-Rooter service has budgeted $5,000 to spend on drain-cleaning equipment. If this money has to pay for the equipment and for any sales taxes that will be added to the price of the item, does the business have 500 dollars left after purchasing the equipment?

(1) The sales tax on the equipment was 10%.

(2) The total price of the equipment was less than $4,000.

Question: \(Eprice+Etax ≤4500?\) If yes, than the biz has 500 left after purchase, if not then it doesn't have 500 left after purchase.

(1) The sales tax on the equipment was 10%. So \(Etax = 0.10*Eprice\), but since we don't know \(Eprice\); insufficient.

(2) The total price of the equipment was less than $4,000. So \(0<Eprice<4000\), but we don't know \(Etax\); insufficient.

(1)+(2). The possible value is: \(Eprice+Etax =3999*(0.10*3999)=~4400<4500\), thus answer is yes, we have 500 left after purchase; sufficient.

(C) is the answer.