The answer is 2 3/20 because if you want to subtract the fractions, the denominators must be the same. both can go into 20, so 2/5 becomes 8/20 and 3/4 becomes 15/20. now its 3 8/20 - 15/20. since you cant subtract like that, you must borrow from the whole number. 3 becomes 2 and 8/20 becomes 18/20. now its 2 18/20 - 15/20. you can do that now, which the answer comes out as 2 3/20.