Answer:
the question is incomplete, so I looked for similar ones
the number of bottles of water remaining as a function of time:
f(x) = -78x + 468
1.3 bottles are sold per minute x 60 minutes per hour = 78 bottles per hour
x = number of hours
the slope is -78
the y intercept is 468
domain = 0 ≤ x ≤ 7.5 hours (from 10 AM to 5:30 PM)
range = 0 ≤ y ≤ 468 bottles
the snack will run out of bottles of water by 4 PM
78x = 468
x = 468 / 78 = 6 hours
if the snack wants to have enough bottles of water to serve all its customers, it will need:
78 x 7.5 hours = 585 bottles of water
