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 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.
More to read
Converting units of time review (seconds, minutes, and hours)
Time units nest inside each other. 60 seconds make 1 minute. 60 minutes make 1 hour. 24 hours make 1 day. 7 days make 1 week. 52 weeks make about 1 year. To change a big unit into a small one, multiply. 3 hours 25 minutes is 3 x 60 + 25 = 205 minutes. 8 weeks 3 days is 8 x 7 + 3 = 59 days. To change a small unit into a big one, divide and keep the leftover. 150 seconds is 2 minutes with 30 seconds left over. Mixed amounts always need two moves: convert the big part, then add the small part.
Explore more
2 · Watch
Take it off screen
Where it sits
Learn first
This opens up
Where this leads
16 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.