Time

4 minQuiz at the end

Time Units

UnitEquivalent
1 minute60 seconds
1 hour60 minutes = 3,600 seconds
1 day24 hours
1 week7 days
1 year365 days (366 in a leap year)

12-Hour vs 24-Hour Clock

12-hour clock: uses am (midnight to noon) and pm (noon to midnight) 24-hour clock: runs from 00:00 to 23:59

12-hour24-hour
12:00 am (midnight)00:00
6:30 am06:30
12:00 pm (noon)12:00
2:35 pm14:35
11:59 pm23:59

Convert pm to 24-hour: add 12 to the hour (for pm times after 12:59)

Calculating Time Durations

Work in steps crossing through whole hours:

Film starts 19:50, lasts 2 hours 25 minutes:

  • 19:50 + 2 hours = 21:50
  • 21:50 + 25 minutes = 22:15

Converting Mixed Time Units

3 days 5 hours to hours:

  • 3 Γ— 24 = 72 hours + 5 hours = 77 hours

2 hours 45 minutes to minutes:

  • 2 Γ— 60 = 120 + 45 = 165 minutes