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1. 12-Hour Clock:
This clock divides the day into two halves: AM and PM.
1:00 AM is 1 hour after midnight
1:00 PM is 1 hour after noon
2. 24-Hour Clock:
This clock counts all the hours of the day from 0 to 23.
It starts at midnight as 00:00 and goes up to 23:59, just before the next
midnight.
1:00 AM is written as 01:00.
1:00 PM is written as 13:00.
(Imagine you have a pizza that you cut into two halves. The first half is
from midnight to noon (12 slices), and the second half is from noon to
midnight (another 12 slices). In a 12-hour clock, you use the same
numbers (1 to 12) twice. In a 24-hour clock, you keep going up to 23.)
Question: If it’s 3:00 PM on a 12-hour clock, what would it be on a 24-
hour clock?
Answer: It would be 15:00 on a 24-hour clock because you add 12 to the PM
time (3 + 12 = 15).
The difference between different time zones
A time zone is a part of the world where everyone sets their clocks to the
same time.
Question: If it’s 3 PM in Tokyo (which is in a time zone that is 9 hours
ahead of London’s time zone), what time is it in London ?
Since Tokyo is ahead, you’ll need to subtract 9 hours from 3 PM!
3 PM in Tokyo minus 9 hours = 6 AM in London.
So, when it’s 3 PM in Tokyo, it’s 6 AM in London.