If you're seeing this message, it means we're having trouble loading external resources on our website.

If you're behind a web filter, please make sure that the domains *.kastatic.org and *.kasandbox.org are unblocked.

Lesson 1: Converting units of time

# Converting units of time review (seconds, minutes, & hours)

Review the size of seconds, minutes, and hours and how to convert between them.  Then, try some practice problems.

### Units of time

Units of time measure how long something lasts. For example, how many seconds can you hold your breath, or how many minutes long is your favorite movie?

## How long are different units?

A second is a short amount of time. It takes about 1 second to turn on a light or open the refrigerator door.
A minute is equal to 60 seconds. It takes about 1 minute to brush your teeth.
An hour is equal to 60 minutes. Extracurricular activities (gymnastics, piano lessons, soccer practice) often last about 1 hour.

## Practice set 1: Estimating time

Problem 1A
• Current
Identify the most reasonable unit to measure the time it takes to bake a pan of cookies.

Want to try more problems like this? Check out this exercise.

## Converting larger units to smaller units

1, start text, space, m, i, n, u, t, e, end text, equals, start color #1fab54, 60, end color #1fab54, start text, space, s, e, c, o, n, d, s, end text
1, start text, space, h, o, u, r, end text, equals, start color #1fab54, 60, end color #1fab54, start text, space, m, i, n, u, t, e, s, end text
To convert larger units to smaller units we multiply the number of larger units by start color #1fab54, 60, end color #1fab54.
Example: Converting hours to minutes
1, start text, space, h, o, u, r, end text, equals, start color #1fab54, 60, end color #1fab54, start text, space, m, i, n, u, t, e, s, end text
start color #11accd, 6, end color #11accd, start text, space, h, o, u, r, s, end text, equals, start color #11accd, 6, end color #11accd, times, start color #1fab54, 60, end color #1fab54, equals, 360, start text, space, m, i, n, u, t, e, s, end text

## Converting smaller units to larger units

To convert smaller units to larger units we divide the number of smaller units by start color #1fab54, 60, end color #1fab54.
1, start text, space, s, e, c, o, n, d, end text, equals, start fraction, 1, divided by, start color #28ae7b, 60, end color #28ae7b, end fraction, start text, space, m, i, n, u, t, e, end text
1, start text, space, m, i, n, u, t, e, end text, equals, start fraction, 1, divided by, start color #28ae7b, 60, end color #28ae7b, end fraction, start text, space, h, o, u, r, end text
Example: Converting seconds to minutes
1, start text, space, s, e, c, o, n, d, end text, equals, start fraction, 1, divided by, start color #28ae7b, 60, end color #28ae7b, end fraction, start text, space, m, i, n, u, t, e, end text
start color #ff00af, 30, end color #ff00af, start text, space, s, e, c, o, n, d, s, end text, equals, start fraction, start color #ff00af, 30, end color #ff00af, divided by, start color #28ae7b, 60, end color #28ae7b, end fraction, equals, start color #6495ed, start fraction, 1, divided by, 2, end fraction, end color #6495ed, start text, space, m, i, n, u, t, e, end text

## Practice set 2: Converting units of time

Problem 2A
• Current
Convert.
11 minutes equals
seconds

Want to try more problems like this? Check out these exercises:
Convert larger units to smaller units
Converting between units

## Want to join the conversation?

• How many seconds are in an hour?
• There are 3600 seconds in an hour. There are 60 seconds in a minute, 60 seconds in an hour, 3600 seconds in a hour, 24 hours in a day, 7 days in a week, 52 weeks in a year, 365 days in a year, 10 years in a decade, 100 years in a century, 10 decades in a century, 100000 years in an eon.
• why would it be seconds = 1/60 of a minute. It would be easier to say minute = 60 seconds?
• I do not really know,but good question
• if you live to be 123 years old how many weeks , days hours, minutes and seconds did you live?
• It would depend on the exact second you are born and the exact second you die.
• for the first section and the third question it says what the average time to pick up the phone is seconds but what if you can't find your phone.Then it can take more than a few seconds. It could take roughly 15 seconds
• I lost my phone so it toke longer to find. (more like 1 hour)
• What I don't understand is that on practice set 2 it asks how many hours are in 6 minutes. I put 0 and got the rest right but 0 wrong because the answer was 1/10. Why can't it just be 0.
• Well 1/10 tenths of an hour is six minutes but i understand your reasoning
• how many seconds are in an entire year?
• In a "regular" year, there are 365 days. There are 60 * 60 = 3600 seconds in an hour. There are 3600 * 4 = 86400 seconds in a day. Thus, there are 86400 * 365 = 31,536,000 seconds in a regular year.

Now, for a "leap" year, there are 366 days. So, there are 86400 * 366 * 31,622,400 seconds in a leap year.
• think about how old you are now try and think how much Hours you lived :)
• There are a lot of ways to think about time!
All these expressions mean the same thing:
1 year
12 months
52 weeks
365 days
8760 hours
525,600 minutes
31,536,00 seconds.

Not only can you calculate how many hours you've lived, you can also calculate how many years, months, weeks, days, minutes, or even seconds you've lived! Pretty cool! :)