Jonathan goes to bed at 9:30 PM on school nights and wakes up at 6:00 AM. On Fridays and Saturdays, he goes to bed at 11:00 PM and wakes up at 9.00 AM. What is Jonathan's average rate of sleep hours per night?

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Answer 1 · 2018-01-02T14:45:12

#8hrs and 55min#

On school nights, Jonathan sleeps from 9:30 pm to 6:00 am
Which means he sleeps for = #8.5 hrs# on these nights

So his sleep for 5 nights (Mon-Thu and Sun) = #5xx8.5# = #42.5hrs#

On Friday & Saturday, he sleeps from 11:00pm to 9:00 am i.e. he sleeps for #10 hrs# on each of these two days.

So, his total sleep for Friday and Saturday = #2xx10# = #20 hrs#

Now, his total sleep hours for entire week = #42.5+20# = #62.5 hrs#

And his average rate of sleep per night = #62.5/7# = #8.92 hrs#

or, approximately, #8 hrs and 55 min#