Time (III): Minutes

1Summary 重點摘要

Long hand at a number × 5. At 3 = 15 minutes.

2Vocabulary cards Vocabulary

3Step by step Steps

1. Step 1: The clock's minutesThe clock face has the numbers 1 to 12, and the gap between two neighbouring numbers is one big step. One big step of the long hand is 5 minutes. A full trip round the 12 big steps makes 60 minutes in all, which is 1 hour, so 1 hour = 60 minutes. A common mistake is to think one big step is 1 minute, reading the long hand at 4 as 4 minutes. Remember that every number on the face stands for 5 minutes; before reading the minutes, count how many big steps the long hand has taken, then multiply by 5, and the minutes will not be misread.
2. Step 2: Minute hand at 1When the long hand points at 1, it has taken one big step: 1 × 5 = 5, which is 5 minutes. Whichever number the long hand points at, multiply that number by 5; this is the simple way to read minutes: at 2 it is 10 minutes, at 4 it is 20 minutes, at 9 it is 45 minutes. With a little practice you can see it at a glance. A common mistake is to mix up the two hands: the short hand is short and thick, the long hand long and thin. If they are swapped, both the hour and the minutes go wrong. When reading a clock, identify the hands first: the long hand gives minutes, the short hand gives hours; keep this division of labour firmly in mind.
3. Step 3: Minute hand at 3When the long hand points at 3, it has taken three big steps: 3 × 5 = 15, which is 15 minutes. 15 minutes is also called a 'quarter', exactly a quarter of the way round the face. If the short hand has just passed 3, the time is 3:15. A common mistake is to think the long hand at 3 means about 3 minutes, or to take a 'quarter' as a whole hour; a quarter is 15 minutes, and there are four quarters in an hour. When reading a clock, first see which number the short hand has passed to fix the hour, then see the long hand at 3 for 15 minutes; together they give the full time.
4. Step 4: Minute hand at 6When the long hand points at 6, six big steps have been taken: 6 × 5 = 30, which is 30 minutes, half past. At 6 the long hand stands at the bottom of the face, exactly opposite the 12 of the o'clock, and the short hand should be halfway between two numbers: at half past 4 it sits between 4 and 5. A common mistake is to read that as half past 5; at half past the hour the short hand has moved only halfway, so look at the number it has just left. Between 4 and 5 is half past 4, not half past 5, and this is the easiest point to get wrong.
5. Step 5: Minute hand at 8When the long hand points at 8, 8 × 5 = 40, which is 40 minutes. If the short hand has already passed 2, the time is 40 minutes past 2, written 2:40. Read the short hand first for the hour, then the long hand for the minutes; do not swap this order. A common mistake is to read 2:40 as 3:40 because the short hand is near 3; but at 40 minutes it has not reached 3 yet, only drawn close. For the short hand, look at the number it has just gone past, not the one it is approaching; nearly 3 is still after 2.
6. Step 6: Count in fivesInstead of multiplying, count in fives from 12: when the long hand points at 7, count 5, 10, 15, 20, 25, 30, 35 - seven numbers in all, which is 35 minutes. The number of counts matches the number pointed at, so the two methods can check each other. A common mistake is to skip or repeat while counting, jumping straight from 5 to 15. Move a pencil tip round the face one step at a time, saying one number per mark, and nothing will be skipped. Once fluent, use both counting in fives and multiplication, and reading a clock becomes quick and accurate.

4Diagrams Diagrams

5Worked example Example

6Common mistakes Mistakes

7Quick check Quick check

8Recap Recap

• Each number on the clock = 5 minutes.
• Minute hand at n = n × 5 minutes.
• Quarter = 15 min; half past = 30 min.
• Whole face = 60 min = 1 hour.
• Read both hands together.