guys i need help but quick what is 2 3/4-1 1/8 and i need to estimate the diffrent. Help

2 3/4-1 1/8

= 2.75 - 1.125
guess is about 1.6

actual:
11/4 - 9/8
= 22/8 - 9/8
= 13/8 = 1.625