How did you get 75 for the people who are tired and sleep less than 6 hrs..
Its 75% and so so 75% of 80 is 60 and not 75.
Actually, the question says "75% of the interns receive fewer than 6 hours of sleep and report feeling tired during their shifts", this is different from "80% of the interns receive fewer than 6 hours of sleep".
The first statement says the interns are both tired & sleep less whereas the second statement says they only sleep less.
Does this make sense?
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