Mathematics >> Clock

A watch which gains uniformly is 2 minutes low at noon on Monday and is 4 min. 48 sec fast at 2 p.m. on the following Monday. When was it correct?
How many times in a day, the hands of a clock are straight?
How many times do the hands of a clock coincide in a day?
At what time, in minutes, between 3 o’clock and 4 o’clock, both the needles will coincide each other?
At what time between 9 and 10 o’clock will the hands of a watch be together?
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