Alex is saving up for a new car. He already has $14,500 saved up and the car costs $14,600. He decides that to make the last of the money he will deliver groceries for people in the neighborhood. He charges $1.5 per trip and then 5% of the price of the groceries. If he makes 40 trips and has saved up enough, how many dollars' worth of groceries did he deliver? Let's think first. Chain of thought:
He needs to save up $100 because 14,600 - 14,500 = 100. He earned $60 off trips because 40 x 1.5 = 60. He earned $40 off groceries because 100 - 60 = 40. He delivered $800 in groceries because 40 / .05 = 800.
Therefore, the answer is 800.