Final answer:
The rate at which the janitor mops is 1 classroom per 1/5 hour.
Step-by-step explanation:
The rate at which the janitor mops is calculated by dividing the number of classrooms mopped by the time taken. In this case, the janitor mops 1 classroom in 5 minutes. Therefore, the rate at which he mops is 1 classroom per 5 minutes. We can simplify this answer by considering that 5 minutes is equivalent to 1/5 of an hour. So, the rate at which the janitor mops is 1 classroom per 1/5 hour.
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