Question

In the refrigerator there are 3 opened milk bottles. One bottle
contains 3/10 of a gallon, and a second bottle also contains
3/10 of a gallon. If altogether there is 1 3/10 gallons in the
refrigerator, how much milk is in the third bottle?

Answer 1

The answer is 7/10
1 3/10 minus 6/10 equals 7/10