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\ 08-Oct-2025 Bharat Arora Proof-9 Reader’s Sign _______________________ Date __________

1. Two trains depart from Lucknow and arrive at Varanasi as per the timetable given
below.
trAIN dePArtUre tIMe FrOM LUCKNOW ArrIVAL tIMe At VArANASI

SUPER FAST 5:10 p.m. 9:20 p.m.
EXPRESS 1730 hours 2400 hours
How much more time does the Express train take as compared to the Super Fast

train?

THE 24-HOUR CLOCK

We normally use the 12-hour clock to measure time. 2400 hours
The Railways, airlines and some other organisations 2300 hours 0000 hours
or
work day and night which means for 24 hours. At 2200 hours 11 12 1 0100 hours
0200 hours
2
2100 hours
such places a 24-hour clock is used. 2000 hours 9 10 midnight 3 0300 hours
0400 hours
In this system, we use 4 digits to show the time. 1900 hours 8 4 5 0500 hours
The first two digits show the hours and the last two 6 7 p.m. a.m. 6
digits show the minutes. 1800 hours 0600 hours
1700 hours 5 7 0700 hours
A day starts at 12 midnight and is written as 0000 1600 hours 4 8
0800 hours
hours or 2400 hours. 1500 hours 3 2 noon 10 9 0900 hours
12 o’clock midnight is expressed as 0000 hours. 1400 hours 1 12 11 1000 hours
1300 hours 1100 hours
12 o’clock at noon is expressed as 1200 hours. 1200 hours

Conversion of 24-hour Clock Time to 12-hour Clock Time

To convert 24-hour clock time to the 12-hour clock, we follow these rules.
Rule 1: If the 24-hour clock time is between 0100 hours
and 1159 hours, write hours and minutes side by Be Aware
side by separating them with a colon and write a.m. stands for ante meridiem.
p.m. stands for post meridiem.
a.m. next to it.

For example: 0750 hours = 7:50 a.m.
1057 hours = 10:57 a.m.

Rule 2: If the 24-hour clock time is between 1200 hours and 2359 hours, then subtract
1200 hours from the given time. Separate the hours and minutes with a colon.
Write p.m. next to it.
For example: FACTS
( a) 1300 hours = 1:00 p.m. To represent time in the 24-hour
clock format, we can either write the
( 1300 hours – 1200 hours = 0100 hours) four digits (the first two show hours
and the last two show minutes)—side
( b) 2359 hours = 11:59 p.m.
by side or separate the hours and
( 2359 hours – 1200 hours = 1159 hours) the minutes using a colon.

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