+50 A bookstore sells used books at a 40$\%$ discount off the regular price of the book when it was new. The price of a used book is $\$18$. What was the regular price of that book when it was new
+781 40% discount means that the discounted price is 60% of the original. After discount, the used book is $18, which is 60% of its original price, x. We form an equation:
18=60/100(x)
1800=60x
x=$ 30
