have i got this right?

yeah 11/12

= 2 3/12 - 1 4/12
= 2 1/4 - 1 1/3
= 9/4 - 4/3
= 27/12 - 16/12
= 11/12

Answer: 11/12

Checking (back to 2 1/4):
= 11/12 + 4/3
= 11/12 + 16/12
= 27/12 or 9/4 or 2 1/4

since there is a common denominator simply convert it to an improper fraction, then subtract the numerators.

27/12 - 16/12 = 11/12

1 and 11/12

nope, it's 11/12

2 3/12 - 1 4/12
= 1 (3 + 12)/12 - 1 4/12
= 1 15/12 - 1 4/12
= (1 - 1) + (15/12 - 4/12)
= 11/12

1 15/12 - 1 4/12 = 11 / 12

OR

2¼ - 1⅓
9/4 - 4/3
27/12 - 16/12
11/12

OR

1 + 3/12 - 4/12
12/12 + 3/12 - 4/12
15/12 - 4/12
11/12