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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.
Want to learn more about units of time? Check out this video.

Practice set 1: Estimating time

Problem 1A
Identify the most reasonable unit to measure the time it takes to bake a pan of cookies.
Choose 1 answer:

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

Converting larger units to smaller units

1 minute=60 seconds
1 hour=60 minutes
To convert larger units to smaller units we multiply the number of larger units by 60.
Example: Converting hours to minutes
1 hour=60 minutes
6 hours=6×60=360 minutes

Converting smaller units to larger units

To convert smaller units to larger units we divide the number of smaller units by 60.
1 second=160 minute
1 minute=160 hour
Example: Converting seconds to minutes
1 second=160 minute
30 seconds=3060=12 minute
Want to learn more about units of time? Check out this video.

Practice set 2: Converting units of time

Problem 2A
Convert.
11 minutes =
  • Your answer should be
  • an integer, like 6
  • an exact decimal, like 0.75
  • a simplified proper fraction, like 3/5
  • a simplified improper fraction, like 7/4
  • a mixed number, like 1 3/4
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?

  • duskpin sapling style avatar for user Jamie
    How many seconds are in an hour?
    (28 votes)
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    • duskpin seed style avatar for user Cheyenne Kisic
      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.
      (83 votes)
  • male robot donald style avatar for user Collin
    why would it be seconds = 1/60 of a minute. It would be easier to say minute = 60 seconds?
    (35 votes)
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  • primosaur tree style avatar for user kavand
    if you live to be 123 years old how many weeks , days hours, minutes and seconds did you live?
    (23 votes)
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    • area 52 blue style avatar for user Area53
      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.
      (10 votes)
  • ohnoes default style avatar for user Eric Roza
    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
    (16 votes)
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  • starky sapling style avatar for user Keelie
    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.
    (17 votes)
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  • mr pants pink style avatar for user Megan the Magical Mango
    how many seconds are in an entire year?
    (13 votes)
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    • spunky sam red style avatar for user Marvin Cohen
      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.
      (11 votes)
  • blobby blue style avatar for user Shayna Vinoth
    how can we know how many hours is 6 min?
    (12 votes)
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  • spunky sam red style avatar for user Marvin Cohen
    How do you convert from minutes and seconds to months and vice versa? What about to years?
    (4 votes)
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    • duskpin ultimate style avatar for user Polina Vitić
      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
      (8 votes)
  • blobby green style avatar for user Anna Gonzalez
    how to divide 14 hour 15 minute by 10 show working for math thank
    (3 votes)
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    • piceratops ultimate style avatar for user watsonworms
      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?
      Secondly: divide the number by 10 to get your answer.
      Thirdly: if you end up with a decimal number of minutes, remember to convert properly to seconds (60 seconds in a minute!)
      Finally: simplify whatever number you have back into hours and minutes (instead of just minutes).
      (5 votes)
  • blobby blue style avatar for user Julian Mejia
    How many seconds in a year if every month was 30 days long? no leap year thing!!
    (4 votes)
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