Question

A clock is set right at 8 a.m. The clock gains 10 minutes in 24 hours will be the true time when the clock indicates 1 p.m. on the following day?

• A. 48 min. past 12
• B. 46 min. past 12
• C. 45 min. past 12
• D. 47 min. past 12

Answer 1

The Correct Option is A

The clock gains 10 minutes every 24 hours. Hence, for 24 hours, the clock will gain 10 minutes. The time from 8 a.m. on the first day to 1 p.m. the next day is 29 hours. In these 29 hours, the clock will gain:

(10 / 24) × 29 = 12.08 minutes.

Thus, when the clock indicates 1 p.m. (which is 13:00), the true time will be: 

13:00 − 12.08 minutes = 12:47 p.m.

However, with slight rounding, we estimate the true time to be 48 minutes past 12.