What You should do is divide each number by 4 (to get it in 1 dozen and then times it with 10 to get it in 10 dozen)
So I'll do the first one:
2 3/4 can be expanded to 11/4.
(11/4)/(4)
11/(4*4)
11/16
Then you times it with 10
11/16*10
110/16=6 14/16 cups.