# Units of time

### Units of time

#### Lessons

In this lesson, we will learn:

• The different units of time: years, months, weeks, days, hours, minutes, and seconds
• The units of time for many years: decades, centuries, millennia
• How to convert between the different units of time

Notes:

• Units of time are intervals of time that measure duration
• The most common units of time that we see are: years, months, weeks, days, hours, minutes, and seconds

• Even longer intervals of time include: decades, centuries, and millennia

• When converting between different units of time:
• Multiply when changing from bigger to smaller time units
• Divide when changing from smaller to bigger time units
• Use the conversion list of equivalent times:

• Examples:

• Introduction
Introduction to Units of Time:
a)
What are the different units of time?

b)
When to multiply or divide when converting units of time.

c)
How to convert between different units of time.

• 1.
Common Durations of Time
Which unit of time should you use to describe the following?
• Listening to a song?
• Watching a movie?
• Typing a question into a website browser?

• 2.
Converting Units of Time in a Table
Fill in the table to convert between different units of time.
a)
Minutes and seconds

b)
Hours and minutes

c)
Days and hours

d)
Weeks and days

• 3.
Converting Between Different Units of Time
Fill in the blanks by converting the times
a)
Between seconds, minutes and hours
5 min = ____s $\qquad$ ____min = 2 h $\qquad$ 1 h = ____s $\qquad$ ____h = 240 min

b)
Between hours, days and weeks
4 d = ____h $\qquad$ ____wk = 35 d $\qquad$ 1 wk = ____h $\qquad$ ____h = 3 d

c)
Between months, years, decades, centuries and millennia
2 y = ____mo $\qquad$ __decades = 20 y $\qquad$ 5 centuries =__y $\qquad$ __millennia = 8000 y

• 4.
Comparing Different Units of Time
Which amount of time is longer? Show your work; convert times into the same units to compare.
a)
90 min OR 1 h 40 min

b)
267 s OR 5 min 4

c)
126 h OR 4 d 21 h

d)
28 d OR 3 wk 5 d

e)
30 mo OR 2 y 5 mo