Question

subtract 3 by 20 from 11 by 4

Answer 1

simply subtract the following

The answer is 2 3/5
That is 2.6

Answer 2

11/4-3/20
LCM of 4 and 20 is 20
55-3/20=52/20=26/10=2.6
                     or
    52/20=26/10=13/5

hope it helps