Convert the rate 1000 fluid ounces per 2 hours to cups per minute

There are 8 ounces in a cup, so there are 125 cups in 1000 ounces.
1000 / 8 = 125
there are 60 minutes in an hour and 120 minutes in 2 hours
so 1000 ounces / 2 hours is
125 cups / 120 minutes
125 / 120 = 1.04 cups per minute

Check your work
multiply times 60 to get cups per hour
1.04 * 60 = 62.4 cups per hour
multiply times 8 to get ounces per hour
62.4 * 8 = 499.2
multiply times 2 to get ounces per 2 hours
499.2 * 2 = 998.4
the number is not quite 1000 due to rounding the 125 / 120 as it is closer to 1.041666666666667