94. 7 pounds of grapes costs 10.43 dollars. Now, solve for the costs of 3 pounds of grapes. There are different ways to solve this kind of situation. For my end, I will be showing the solution that I think is easier. => 7 pounds = 10.43 dollars. Find the unit rate first => 10.43 dollars / 7 = 1.49 dollars per pounds. Now, solve for the cost of 3 pounds => 1.49 * 3 = 4.47 dollars is the costs of 3 pounds of grapes.