Answer:
Sally would need at least 235 gallons of sunblock.
Step-by-step explanation:
We can solve this problem be setting up an equation to first find the number of total ounces needed for all the bottles filled in 10 hours and then converting ounces to gallons. Since the machine can fill 150 bottles an hour, and each bottle takes 20 ounces, our equation could be set up like this:
20(150 x 10) = x, where x = number of ounces
20(1500) = 30000 ounces
Since there are 128 ounces per gallon, we would then divide the total number number of ounces by 128: 30000 ÷ 128 = 234.375 gallons. Assuming we would have to use full gallons, we would round to the nearest whole number - 235 gallons.