Answer:


And then the percentage between 24 and 40 would be 
Step-by-step explanation:
For this problem we have the following parameters given:

And for this case we want to find the percentage of lightbulb replacement requests numbering between 24 and 40.
From the empirical rule we know that we have 68% of the values within one deviation from the mean, 95% of the values within 2 deviations and 99.7% within 3 deviations.
We can find the number of deviations from themean for the limits with the z score formula we got:

And replacing we got:


And then the percentage between 24 and 40 would be 