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E:\Working\Orange_Education\Math_Genius_4\Open_Files\Chap-11
\\September 30, 2025 12:00 PM Bharat Arora P-9 Reader _________________________ Date: ___________________74
3. rewrite the following statements using the 12-hour clock.
(a) Renu wakes up at 06:45 hours.
(b) A bus leaves ISBT at 14:45 hours.
(c) A hawker starts distributing newspapers at 05:35 hours.
(d) A match starts at 17:30 hours.
(e) Golu reached Agra at 20:10 hours.
4. Rehan goes out to play at 4:30 in the evening. How can we read this time in a
12-hour clock and a 24-hour clock format?
conveRsion of units of time
We know that:
1 hour = 60 minutes or 60 minutes = 1 hour
1 minute = 60 seconds or 60 seconds = 1 minute
To convert hours into minutes, we multiply the number of hours by 60.
To convert minutes to seconds, we multiply the number of minutes by 60.
example 1: Convert the following:
(a) 13 minutes into seconds (b) 24 minutes 32 seconds into seconds
(c) 4 hours 8 minutes into minutes
(d) 2 hours 15 minutes 18 seconds into seconds
Solution:
(a) 1 minute = 60 seconds
13 minutes = 13 × 60 seconds
= 780 seconds
(b) 1 minute = 60 seconds
24 minutes = 24 × 60 seconds
= 1440 seconds
24 minutes 32 seconds
= 1440 seconds + 32 seconds
= 1472 seconds
teacher’s Explain to the students that, to convert hours to minutes, we multiply the hours by 60 and to convert minutes
tip to seconds, we multiply the minutes by 60. Similarly, to convert hours to seconds, we multiply the hours by
60 × 60 = 3600.
206 Mathematics-4
