If the time is currently 1:30 pm, what time will it be in exactly 647 hours?
A. 12:30 am
B. 1:30 am
C. 12:30 pm
D. 2:30 pm
E. 10:30 pm

(C) If we divide 647 by 24, not arriving at a decimal, but rather keeping the answer in terms of an integer and the remainder, this number will represent the number of days and hours later that 647 hours is:
647/24 = 26, remainder 23.
Therefore, 647 hours from now is the same as 26 days and 23 hours from now.

The time will be exactly 1 hour earlier in the day, so it will be 12:30 pm.
The correct answer is choice (C).
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It is currently 1:30 pm, which is the same time as 13:30 am. Add 23 hours and one gets 12:30am. Answer A.

If you convert the question into 24-hour clock system, it will be:


If the time is currently 13:30, what time will it be in exactly 647 hours?
A. 00:30
B. 1:30
C. 12:30
D. 14:30
E. 22:30

One hour before 13:30 is 12:30 (which is the same as 23 hours after 13:30). The correct answer is C.

Note, the 24-hour clock system does not have "am" and "pm" abbreviations.