Mariana tried to drink a slushy as fast as she could. She drank the slushy at a rate of 4.5 millimeters per second. After 17 seconds, 148.5 milliliters of slushy remained. how much slushy was originally in the cup?

Since she drank 4.5 mm of slushy per second, she continued to drink for 17 seconds so 4.5•17=76.5

Now that you have how much she drank, add that to how much is remaining (148.5) and the original amount that she drank; the answer is 225 milliliter of slushy