Question

how do you determine if 2/3 is greater than 7/8

Answer 1

The smaller denominator will give a larger fraction. Another method for comparing is to think of the fractions. In this example it is obvious that 1/3 is smaller than 7/8. For one thing, 1/3 is smaller than 1/2 and 7/8 is larger than 1/2.
so therefore 2/3 is not greater than 7/8
2/3 only equal .66
7/8 equals .875

Answer 2

You find a common denominator between the 2 fractions first.

2/3 • 6 = 12/18
7/8 • 2 = 14/18

So, 7/8 is greater than 2/3.