I believe the rule is add 3/8 and the answer would be 2 4/8 or 2 1/2.. if you want help using the patterns then here is an example:
1 1/4, 1 1/2, 1 3/4, 2, ___,___,___,
Recall that 1 1/2 can be expressed as 1 2/4. So if you wanna find the rule just subtract 1 2/4 from 1 1/4.
Hope this helped
