Answer:
The answer to this question would be (to my best guess), 36 hours.
Step-by-step explanation:
First
You have to find the ratio between 87.5% and 100%. This is because you want to find what 100% represents.
To do this, you have to divide 100 by 87.5, which would represent 100 divided by 87.5. This will equal 1.142857142857143 , which isnt an easy number to work with.
Lastly
You have to multiply 1.142857142857143 by 31.5, because you reverse the previous operation, but the only difference is you swap out the percentages with the numbers they represent. This equals the final answer, which is 36, representing 36 hours.