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Converting Units of Time
In order to convert units of time, you must first know how these units relate to each other.
Time Relationships
- 60 seconds = 1 minute
- 60 minutes = 1 hour
- 24 hours = 1 day
- 7 days = 1 week
- 12 months = 1 year
- 52 weeks = 1 year
- 365 days = 1 year (366 for leap years)
- 10 years = 1 decade
- 100 years = 1 century
- 1000 years = 1 millennium
Conversion rule
Large to small: Multiply
Small to large: Divide
This means that if you take a larger unit and convert it to a smaller unit, you must multiply. But if you take a smaller unit and convert it to a larger one, then you must divide.
Let's take a look at some examples:
Example 1
How many hours are in 8 days?
Solution
We want to convert 8 days into hours. Days are larger than hours, and since we are going from large to small, we must multiply.
There are 24 hours in a day, so we will multiply 8 by 24.
8 x 24 = 192
Answer: There are 192 hours in 24 days.
Example 2
Adam's dad has been alive for 60 years. How many decades is that?
Solution
We have to convert 60 years into decades. Years are smaller than decades, so we are going from small to large. That means, we must divide.
Since there are 10 years in a decade, we'll divide by 10.
60 ÷ 10 = 6
Answer: Adam's dad has been alive for 6 decades.
Example 3
How many seconds are in 4 hours?
Solution
We'll just do the conversion in two steps:
Convert hours to minutes and then minutes to seconds.
To convert 4 hours to minutes we must first realize that we're going from large to small, so we'll multiply.
There are 60 minutes in an hour, so we'll multiply by 60.
4 x 60 = 240. There are 240 minutes in 4 hours.
Now we need to convert 240 minutes to seconds.
Since there are 60 seconds in a minute, so we will multiply it by 60.
240 x 60 = 14,400
Answer: Hence, there are 14,400 seconds in 4 hours.
Converting Units of Time
Time conversions:
- 60 seconds = 1 minute
- 60 minutes = 1 hour
- 24 hours = 1 day
- 7 days = 1 week
- 12 months = 1 year
- 52 weeks = 1 year
- 365 days = 1 year (366 for leap years)
- 10 years = 1 decade
- 100 years = 1 century
- 1000 years = 1 millennium
Conversion rule:
Large to small: Multiply
Small to large: Divide