The regular price of a shirt at a store is $11.70. The sale price of the shirt is 80% less than the regular price, and the sale price is 30% greater than the store's cost for the shirt. What was the store's cost, in dollars, for the shirt?

Explanation

The correct answer is 1.8. It's given that the regular price of a shirt at a store is $11.70, and the sale price of the shirt is 80% less than the regular price. It follows that the sale price of the shirt is $11.70 (1- 80/100), or $11.70 (1 - 0.8), which is equivalent to $2.34. It's also given that the sale price of the shirt is 30%greater than the store's cost for the shirt. Let x represent the store's cost for the shirt. It follows that 2.34 = (1+30/100)x, or 2.34 = 1.3x. Dividing both sides of this equation by 1.3 yields x =1.80. Therefore, the store's cost, in dollars, for the shirt is 1.80. Note that 1.8 and 9/5 are examples of ways to enter a correct answer.