Can anyone give me an equation for this problem? I don't understand...

Question

A bookstore owner offered a sale on books that had not sold in 2 years. The before tax price on paperback books was reduced to 2.99 each. The before tax price on hardback books was reduced to 3.49 each. The owner sold 60 more paperback books than hardback books for a total sale of 795, before taxes. How many paperback books were sold?

Answer 1

Let P be the number of paperbacks and H be the number of hardcovers.

 

P = H + 60 <--- they sold 60 more paperbacks than hardcovers

 

$2.99*P + $3.49*H = $795 <--- total sales were $795

 

Multiplies the second equation by 100 to clear the decimals:

 

299*P + 349H = 79500

 

299*(H+60) + 349*H = 79500

 

299*H + 17940 + 349*H = 79500

 

648*H + 17940 = 79500

 

H = (79500 - 17940)/648

 

H = 95

 

P = 155

 

2.99 x 155 + 3.49 x 95 = 795

 

155 Paperbacks and 95 hardcovers.

Answer is checked, verified, and proven to be correct

Answer 2

sale of hardback bag = x

sale of paperback bag =x+60

 

3.49x +2.99(x+60) = 795