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Lesson 8: 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
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

To convert larger units to smaller units we multiply the number of larger units by $60$.
Example: Converting hours to minutes

## Converting smaller units to larger units

To convert smaller units to larger units we divide the number of smaller units by $60$.
Example: Converting seconds to minutes

## Practice set 2: Converting units of time

Problem 2A
Convert.
$11$ minutes $=$
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?
• If you are talkimng about the very first moment of january 1st which is 0 seconds then if you were born on that time it would be approxiamately . Nowe we find the amount of days in a year which is 365 days. WAIT WOAH WOAH WOAH. Ok this is theoritically impossible to solve due to our menacing opponent... The leap year. If we dont know what year it was and when the last leap year was then this is a immposible question to solve. We dont require enough information for this. SO your answer is immpossible to solve. Even though you probably are in highschool please give us when the last leap year was.
• 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.
• how can we know how many hours is 6 min?
• 6 minutes is not enough time for their to be an hour because an hour requires 60 minutes. Therefore if you were do divide 6(minutes) by 60 you would get 0.1, That being the amount of hours in 6 minutes.
• How do you convert from minutes and seconds to months and vice versa? What about to years?
• Just convert the units!

For instance:
1000 min x (1 hr / 60 min) x (1 day / 24 hr) x (1 month / 30.5 days)
= 1000 / (60 x 24 x 30.5) months
= 0.02277 months

So 1000 minutes = 0.02277 months

Also:
1 month x (30.5 days / 1 month) x (24 hr / 1 day) x (60 min / 1 hr) x (60 sec / 1 min)
= (1 x 30.5 x 24 x 60 x 60) sec
= 2,635,200 sec

So 1 month = 2,635,200 seconds

And:
0.02277 months x (1 year / 12 months)
= 0.001898 years

So 1000 minutes = 0.001898 years
• How many milliseconds are in an hour. How many minutes are in a year?
• There are 1,000 milliseconds in a second, 60 seconds in a minute, and 60 minutes in an hour.
So there are 1,000 * 60 * 60 = 3,600,000 milliseconds in an hour.

There are 60 minutes in an hour, 24 hours in a day, and 365 days in a regular (non-leap) year.
So there are 60 * 24 * 365 = 525,600 minutes in a regular (non-leap) year.
• how to divide 14 hour 15 minute by 10 show working for math thank
• Hey Anna, the trick when working with time is to remember that there are 60 seconds in a minute and 60 minutes in an hour. So you don't want to, for example, divide 1 hour 30 minutes by 10 and try to use the equation 1.3/10 = 0.13 and say you have 13 minutes. Instead, you need to convert the original 1 hour and 30 minutes to minutes. With 60 minutes in an hour, 1 hour and 30 minutes = 60 minutes + 30 minutes = 90 minutes. 90 minutes divided by 10 gives you 9 minutes. (Not 13!)

So!
First: how many minutes do you have when you start with 14 hours and 15 minutes?