61.--CHANGING PLACES.

[Illustration]

The above clock face indicates a little before 42 minutes past 4. The

hands will again point at exactly the same spots a little after 23

minutes past 8. In fact, the hands will have changed places. How many

times do the hands of a clock change places between three o'clock p.m.

and midnight? And out of all the pairs of times indicated by these

changes, what is the exact time when the minute hand will be nearest to

the point IX?

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