Answer:
Explanation:
Total Minutes
The fan can achieve 1,000,000,000 rotations in its lifetime and does 700 rotations per minute
Therefore, the fan will work for [tex]\frac{1,000,000,000}{700}[/tex] = 1,428,571.45 minutes in its lifetime.
Working Time
Andre works for 9 hours, assuming he sleeps for 8 hours, The fan is on for 7 hours on weekdays (25 - 9 - 8), a total of 35 hours and
16 hours on the weekend (24 - 8), a total of 32 hours
The fan is on for 67 hours a week or 4020 minutes.
Downtime
Everyday the fan is used, it takes 5.0 seconds to get to its full speed and 7.0 seconds for the blade to stop, an additional 2 seconds per day. This adds 14 seconds per week.
In a week, the fan works for 4020 minutes + ([tex]\frac{14}{60}[/tex])
=4020.23minutes
In its lifetime, the fan will work for [tex]\frac{1,428,571.45 }{4020.23}[/tex] weeks.
=355.35 weeks
OR 355.35 X 7 Days
2487 hot days
