Answer:
32.4
Step-by-step explanation:
prior + 8.1 = 40.5 . . . . . . seems to model the problem statement
prior = 32.4 . . . . . . . subtract 8.1 from both sides
Prior to the increase the percent was 32.4.
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<em>Comment on the problem statement</em>
When you're talking about a percentage increase in a percentage, it is almost never clear whether you're talking about the percentage of the underlying number, or the percentage of the percentage.
Here, we assume the 8.1 is a percentage of working students, not a percentage of the percentage of workings students. If you actually intend the latter, the percentage before the increase was about 37.465%.
