Oh. It's rounding. So, for example, depending what you were told to round to, the second problem would be 760-330=430
10.05 = 10 5/100 = 10 1/20
10.005 = 10 5/1000 = 10 1/200
therefore, 10.05 is greater then 10.005
6 quarts of water is 1.5 gallons if that's what you are looking for