Converting time units
Solve problems involving converting between units of time (hours↔minutes, minutes↔seconds, years↔months, weeks↔days)
What a learner can do afterwards
- Convert 3 hours 25 minutes to 205 minutes
- A programme lasts 150 seconds — express in minutes and seconds
- How many days are in 8 weeks and 3 days?
1 · Read
You already know how to change centimeters into meters and grams into kilograms. Time units work the same way. Each unit breaks into a fixed number of smaller units: 60 seconds make 1 minute, 60 minutes make 1 hour, 7 days make 1 week, and 12 months make 1 year.
To convert 3 hours 25 minutes into minutes, first turn the hours into minutes: 3 hours × 60 = 180 minutes. Then add the leftover 25 minutes: 180 + 25 = 205 minutes in total.
To go the other way, change seconds into minutes. 150 seconds has two full 60s inside it: 150 ÷ 60 = 2, with 30 left over. That means 150 seconds is 2 minutes and 30 seconds.
The same idea works for weeks and days. For 8 weeks and 3 days, multiply the weeks first: 8 × 7 = 56 days, then add the 3 extra days: 56 + 3 = 59 days. Multiply to reach smaller units, then add any leftovers.
Multiply to change a bigger time unit into a smaller one, divide to change a smaller unit into a bigger one, and always deal with the leftovers separately.
2 · Watch
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Where it sits
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Where this leads
8 questions wait behind this lesson, each with its answer explained. Every answer feeds the sky: stars light as they are learned, and dim when it is time to come back.