Jimmy is selling used books at a yard sale. a customer buys 9 books at a cost of $0.75 each and pays with a $20.00 bill. jimmy must determine c, the amount of change in dollars he should give the customer. which equation represents c? 20-0.75c=9 20-0.75=9c 0.75(9)+c=20 0.75c+9=20

Let r = 3. what is the value of r + 58?

Amerchant has coffee worth $60 a pound that she wishes to mix with 50 pounds of coffee worth $90 a pound to get a mixture that she will sell for $70 a pound. how many pounds of the & 60 coffee should be used?

The average number of vehicles waiting in line to enter a parking lot can be modeled by the function f left parenthesis x right x squared over 2 left parenthesis 1 minus x right parenthesis endfraction , where x is a number between 0 and 1 known as the traffic intensity. find the rate of change of the number of vehicles waiting with respect to the traffic intensity for the intensities (a) xequals0.3 and (b) xequals0.6.