Harvey has a fair eight-sided die that has a different number from 1 to 8 on each side. if he rolls the die twice, what is the probability that the second number rolled is greater than or equal to the first number? express answer as a common fraction.

It depends on what the first roll was

On the first roll, every number has a 1/8 chance to be rolled

On the second roll, a lower number on the first roll has a greater chance to have a higher number rolled  or the same number the second time.

First roll is...
1 : probability to be out rolled or equal roll 8/8 or 1/1
2 : probability to be out rolled or equal roll 7/8
3 : probability to be out rolled or equal roll 6/8 or 3/4
4 : probability to be out rolled or equal roll 5/8
5 : probability to be out rolled or equal roll 4/8 or 1/2
6 : probability to be out rolled or equal roll 3/8
7 : probability to be out rolled or equal roll 2/8 or 1/4
8 : probability to be out rolled or equal roll 1/8

Hope this helps :)