(5 7/8-6 3/4)-2 1/4
Solve the numbers in the parenthesis ( I change the denominators to a common denominator that 8 and 4 share)
(5 7/8 - 6 3/4)-2 1/4
^
-1 1/8-2 1/4
(I use KKC aka Keep Change Change where I keep -1 1/8 the same, change the minus sign to a plus sign, and change the -2 1/4 to positive) ( I change the denominators to a common denominator that 8 and 4 share)
-1 1/8 + +2 1/4 = 1 1/8