Units of time
We measure time with different units. Bigger units are made of many smaller units. Knowing how they link lets us change from one unit to another.
Key idea
1 minute = 60 seconds · 1 hour = 60 minutes · 1 day = 24 hours · 1 week = 7 days · 1 year = 12 months.
Changing units
To change a bigger unit into a smaller one, we multiply. For example, hours to minutes means multiplying by 60.
Worked example
How many minutes are in 2 hours? Since 1 hour = 60 minutes, we multiply: 2 × 60 = 120 minutes.
To go the other way, from a smaller unit to a bigger one, we divide. For example, how many hours are in 120 minutes? We divide by 60: 120 ÷ 60 = 2 hours. Multiplying and dividing are opposites, so we can always check one with the other. This is very useful when comparing two times given in different units.
Remember
- 1 week = 7 days.
- 1 day = 24 hours.
- Bigger to smaller: multiply.
- Smaller to bigger: divide.