Answer:
53
Step-by-step explanation:
When I entered 53 into PLATO, it appears to be the correct answer.
The last part of the question is asking;
What was the total amount spent by all (99.7%) students on textbooks in a semester?
Response:
almost all (99.7%) of the students spent between $165 and $315 on textbooks in a semester.
Stepwise clarification:
The standard deviation rule informs that for normally distributed data, approximately 99.7% of observations fall within three standard deviations from the mean.
In this case, we have the given mean as 240, and standard deviation as 25
Thus, calculating three standard deviations below the mean: Mean - 3(standard deviation)
equals 240 - (3 × 25)
yielding 240 - 75 = 165
Now, for three standard deviations above the mean: Mean + 3 (standard deviation) = 240 + (3 × 25)
equals 240 + 75 = 315
Therefore, nearly all (99.7%) of the students spent between $165 and $315 on textbooks in a semester.
