P4 Maths: 24-Hour Time Calculations (Paper 1 (basics))

2026-11-15

Tutor Prep Guide · am/pm and 24-hour conversion; durations across noon and midnight; minute carrying; everyday timetables

Paper 1 (basics): ten time questions on am/pm and 24-hour conversion, durations across noon and midnight, and minute carrying, with answers and one-line notes.

Direct answers　Level: P4 maths; format: am/pm and 24-hour conversion, durations, spans across midnight, and minute carrying or borrowing.

01　Paper details (check answers afterwards)

Item	Detail
Questions	10
Suggested time	20
Difficulty mix	Foundation 3 · Intermediate 3 · Challenge 3 · Error redo 1
Chapter	Chapter: P4 Maths: 24-Hour Time Calculations
Level	P4

02　Questions (10 items)

FoundationWhat is 3:00 pm in 24-hour time?
FoundationWhat is 9:30 am in 24-hour time?
FoundationWhat is 20:00 in 12-hour time?
IntermediateWhat is 11:45 pm in 24-hour time?
IntermediateWhat is 07:15 in 12-hour time?
IntermediateWhat is midnight, 12:00 am, in 24-hour time?
ChallengeHow long is it from 09:00 to 11:00?
ChallengeHow long is it from 14:30 to 16:30?
ChallengeHow long is it from 8:00 am to 10:30 am?
Error redoA pupil writes 3:00 pm as 03:00. What is wrong?

03　Answers and one-line notes

#	Answer	One-line note
1	15:00.	Add 12 to an afternoon hour: 3 + 12 = 15, so it is written 15:00.
2	09:30.	Morning times are written as they are, with two digits for hours and minutes: 09:30.
3	8:00 pm.	Subtract 12 when the hour passes 12: 20 – 12 = 8, so it is 8:00 pm.
4	23:45.	Add 12 to the hour: 11 + 12 = 23, and the minutes stay, giving 23:45.
5	7:15 am.	An hour below 12 is in the morning, so 07:15 reads as 7:15 am.
6	00:00.	Midnight starts a new day, so 24-hour time writes it 00:00, not 12:00.
7	2 hours.	Subtract the hours: 11 – 9 = 2, and both times fall on the same day.
8	2 hours.	The minutes match, so subtract the hours only: 16 – 14 = 2.
9	2 hours 30 minutes.	From 8:00 to 10:00 takes 2 hours, then add 30 minutes, giving 2 hours 30 minutes.
10	The 12 was not added; it should be 15:00.	03:00 means 3 in the early morning; an afternoon hour must have 12 added, giving 15:00.

04　What to do after marking

After marking, redo only the wrong items and write down which step went wrong (formula, unit, or misread number).
Repeat the same item two days later; move to the next paper only when both attempts are correct.
Parents only need the answer and note columns; there is no need to explain every item.

Check the answers; for a wrong duration, write both times down and subtract them in steps.Tutor Registration →

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