Package #1 = 5/8
Package #2 = 2/3
So for both fractions (5/8 and 2/3), we need to have a common denominator. In this case, the common factor of 8 and 3 is 24.
1. Multiply 5/8 by 3

2. Multiply 2/3 by 8

3. Simplify


The total weight of the two packages is
1 and 7/24
Package #1 = 15/24
Package #2 = 16/24
Subtract:

The second package is
1/24 heavier than the first package.