Q. How many times do the hands of a clock coincide in a day ?

The correct answer is: d) 22

Explanation: The hands of a clock coincide (overlap) when the minute hand and the hour hand are at the same position. This happens once every hour. For example, the hands coincide at 12:00, 1:05, 2:10, and so on.

In one complete cycle of 12 hours, the hands of the clock coincide 11 times. This is because the hands coincide at 12:00, but after that, they coincide once in each subsequent hour until they reach 11:00. At 12:00 again, the cycle repeats.

Now, in a full day, there are 24 hours. Since the hands coincide 11 times in 12 hours, in 24 hours (a full day), the hands will coincide twice as many times:

11 coincidences in 12 hours x 2 = 22 coincidences in 24 hours.

Therefore, the correct answer is: Option D: 22