# math

posted by Johnny

6. If each of eight biology classrooms is in use for 5 hours and 15 minutes per day, and total of 84 student experiments are done, how long does each experiment take on average?

A.20 minutes
B.30 minutes
C. 40 minutes
D.50 minutes
E.1 hour

1. Reiny

8 hrs, 15 minutes = 315 minutes
total minutes available for the experiments
= 8(315) = 2520 minutes

84 experiments take 2520 minutes
1 experiment takes 2520/84 or 30 minutes

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