Question

In one day, a book store earned $143 in sales for 4 copies of a new cookbook and 5 copies of a new science fiction novel. On the next day, it earned $110 in sales for 3 copies of the cookbook and 4 copies of the science fiction novel. What was the price of each book?

Answer 1

Let the price of a cookbook be x and that of a science fiction be y

Step 1: convert the statements to equations

First statement:

$4x\text{ + 5y = 143}$

Second statement:

$3x\text{ + 4y = 110}$

Step 2: Solve the