This answer is not intended to be insulting, but the question, as posed, doesn't really make sense.
The answer to the question "What is 20% of 87.99?" is:
20 percent of 87.99 is 17.598
98% of 8799 = 98% * 8799 = 0.98 * 8799 = 8,623.02
25
24
3.35
7.5
0.15
500%.
20
0.0048
2.5
801 / 20% = 4,005
0.7143