Telling Time
Measuring Time 2
This week you have several activities to complete in this workbook including...
Knowledge
Measuring Practice
Investigations
Problem solving
We are learning to...
Units of Time - What are they?
Time can be measured in many different units.
They have been adjusted over the years to what we have today where ‘seconds’ are the base unit of measure.
Here are the units of time in increasing order:
Seconds → Minutes → Hours → Days →
Weeks → Months → Years →
Decades → Centuries
These units relate to other like this:
1 minute = 60 seconds
1 hour = 60 minutes
1 day = 24 hours
1 week = 7 days
1 year = 12 months = 52 weeks = 365 days
1 decade = 10 years
1 century = 100 years
Units of Time Knowledge 1
What unit of time would you use to measure each of the following:
Units of Time Knowledge 2
How many?
1) Minutes in an hour?
2) Days in a week?
3) Months in year?
4) Minutes in a day?
5) Seconds in an hour?
6) Days in a leap year?
7) Hours in a week?
8) Minutes in an hour and a half?
How many?
9) Days in the first six months of the year?
10) Hours in a day?
11) Months in quarter of a year?
12) months in two years?
13) Hours in three days?
14) Years in a decade?
15) Years in a century?
16) Days in November?
17) Days in March?
Units of Time Knowledge 3
How many?
18) Days in February in a leap year?
19) Days in an ordinary year?
20) Seconds in a minute?
21) How many minutes are there in
a) 2 hours
(b) half an hour
(c) ½ a day
d) 1 ¼ hours
(e) 5 hours
22) How many hours are there in
a) 4 days
(b) 2 weeks
(c) January
23) How many seconds are there in
a) 3 minutes
(b) 8 minutes
(c) 2 hours
24) How many days are there in
a) 4 weeks
Telling 12 hour Time
Understanding Digital Time
Each calendar day has a total of 24 Hours in it. The 12 hour method of telling time divides this into two equal time periods.
a.m - before midday
p.m - after midday
In order to communicate 12 hour time correctly you need to put the letters am or pm after the time.
TIps for reading the time correctly
Telling 12 hour Time Practice
Write these spoken times in 12 hour time, include am/pm
Write how you would read these 12 hour times
Telling 12 hour Time
Reading Analogue Time
There are 60 minutes in one hour.
It takes the longer hand (minute hand) 60 minutes to move around the clock.
Beginning at 12, when the long hand reaches 1, it has moved 5 minutes. When it reaches 2, it has moved 10 minutes.
It takes 5 minutes for the long hand to move from one number to the next.
12 x 5 mins = 60 minutes = 1 hour.
The shorter hand (hour hand) tells the hour.
Analogue Time Practice
What digital time is being shown on each clock face?
1.
2.
3.
4.
5.
6.
7.
8.
9.
10.
Telling 24 hour Time
Understanding and Reading 24 hour Time
Many countries do not split the 24 hour day into two 12 hour periods but instead they read it from 0 to 23 hours. It is also used in some jobs where it is important that the communication of time is very clear e.g The military and emergency services.
Important Points
To change 24 hour time into pm 12 hour time, subtract 12 from the first two digits.
Example 1
Convert from 24 to 12 hour time
1545 = (15 - 12) :45pm = 3:45pm
1545 = 3:45pm
To change 12 hour pm time to 24 hour time add 12 to the pm hours.
Example 2
Convert from 12 to 24 hours
6:28pm = (6 + 12) :28 = 18:28
Telling 24 hour Time Practice
Write the 24 hour time for each of these and state if it is before or after midday
Write these 24 hour times in 12 hour time
Write the 12 hour time for these 24 hour times
Time Maths Investigation 1
Activity | Estimate | Actual |
Count backwards from 100 - 1 | | |
Complete 10 star jumps | | |
Walk to Nga Manawa and back | | |
Write the 3 x table out correctly | | |
| | |
| | |
Task: Work with a partner to estimate how long it would take you to do each of the following activities. Add two ideas of your own. Once you have estimated complete each of the activities and use the stopwatch on your chromebook to measure accurately how long they took you.
Were your estimates accurate? Why/why not? Write up your investigation and share your findings on your blog.
Time Maths Investigation 2
Time has been measured by many civilisations in many different ways. Read this article here for some interesting information and useful links.
Now choose one of theses methods below to investigate.
Create a DLO to share your findings on your blog. Include who, what, where, when, why and how about your early time telling method as well as visual information. Be creative.
Create a DLO to share your findings.
Problem Solving 1
Problem 1: A pizza needs to be heated for 25 minutes. The oven clock says it is 1748 when you put the pizza in the oven. What time does it say when the pizza is ready?
Insert a photo here of your working out
What operations will solve this problem and why?
Explain how you got your answer in sentence form.
Problem Solving 2
Problem 2: A movie showing on TV starts at 8:25 pm and finishes at 10:54pm. How long does the movie go for?
Insert a photo here of your working out
What operations will solve this problem and why?
Explain how you got your answer in sentence form.
Problem Solving 3
Problem 3: Mr B went out fishing at 6.30am and arrived home at 10 past 8 at night. How long was he out fishing for?
Insert a photo here of your working out
What operations will solve this problem and why?
Explain how you got your answer in sentence form.
Problem Solving 4
Problem 4: Mrs P went to Christchurch in the weekend. She left home at 11.15am and the journey took 2 hours and 47 minutes. What time did she arrive in Christchurch?
Insert a photo here of your working out
What operations will solve this problem and why?
Explain how you got your answer in sentence form.