Week 17 · Word problems with LE, mass and time · 3 lessons
3
Digital time on a clock face
Discover Mathematics P3: Term 2, Lessons 61–70
GoalRead and show digital times on an analogue clock to the minute.
New words
minute hand · the long hand that shows the minuteshour hand · the short hand that shows the hoursdigital time · a time written with numbers, such as 3:25
Explanation
On a clock face, the long minute hand goes all the way round in one hour. Each small mark is 1 minute, and there are 60 marks. The numbers help us count in fives: the 1 means 5 minutes, the 2 means 10 minutes, the 3 means 15 minutes and so on up to the 12, which means 0 minutes. To show a digital time such as 3:25, put the hour hand just after the 3 and the minute hand on the 5, because 25 = 5 × 5. For 8:47, the minute hand is 2 small marks after the 9, because 45 + 2 = 47. The hour hand is then close to the 9 but has not reached it.
Number
Minutes
1
5
2
10
3
15
4
20
5
25
6
30
7
35
8
40
9
45
10
50
11
55
12
0
Worked examples
Digital 3:25. The minute hand points to the 5 (5 × 5 = 25). The hour hand is just after the 3.
Digital 8:47. Count 45 minutes to the 9, then 2 more small marks: 45 + 2 = 47. The hour hand is almost at the 9.
Digital 11:09. The minute hand is 4 small marks after the 1, because 5 + 4 = 9. The hour hand is just after the 11.
Class activity
Clock detective. Look at an analogue clock at home three times today. Each time write the digital time. Say where the minute hand points and which number it is nearest to. Count the small marks past that number to check the minutes.
Practice
1
What digital time does the clock show?
The minute hand is on the 7 (35 minutes), so the time is 9:35.
2
Where does the minute hand point at 4:50?
50 minutes is 10 × 5, so the minute hand points to the 10.
3
Write the digital time on the clock.
The minute hand is 2 small marks after the 10, so it is 50 + 2 = 52 minutes. The time is 12:52.
4
Where does the minute hand point at 2:20?
20 minutes is 4 × 5, so the minute hand points to the 4.
5
A clock shows 5:58. How many minutes are there until 6:00?
