This mathematics document discusses units of time including relationships between years, decades, days, and hours. It explains that there are 365 or 366 days in a year, with leap years occurring every 4 years and having 366 days, and that a decade is equal to 10 years. The document also provides examples and questions to help understand converting between different units of time.

1. MATHEMATICS
YEAR 4
UNIT 5 : TIME
PREPARED BY:
NURUL ‘AIN AHMAD NAZRI
1

2. Relationship between units of
time
1 year = 365 / 366 days
1 decade = 10 years
1 day = 24 hours

3. 1 day = 24 hours
12 hours 12 hours
1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23
24

4. 1 year = 365 / 366 days
• How many month in a year?
12 month
• How many days in a year?
365 days or 366 days.
• Why 365 days or 366 days?
• Its occur when that year is a leap year.
• What is a leap year?

5. Leap year
• 1 leap year = 366 days.
• Which is February having 29 days.
• Leap year occurs once in every 4 years.
Example:
2003 is a leap year. When the leap year
occurs again after 2003?
2007

6. 1 decade = 10 years
• How old are u?
• Are you 1 decade?
• This school build on 2003, how decade
this school?

7. Let’s try:- 24 366 12
365 12 6
1) How many hours in a day?________hours
2) How many hours in a half day?______hours
3) How many months in a year?______months
4) How many months in half of year?____months
5) How many days in a year?_____days
6) How many days in a leap year?____days