Convert 54 km/h to m/s.
- 54 × 1000 = 54000 m per hour.
- 54000 ÷ 3600 = 15 m/s.
- Check: 15 × 3.6 = 54 km/h.
Converting rates
Change units without changing the situation.
Use equivalent measurements
1 h = 60 min = 3600 s and 1 km = 1000 m. Conversion factors represent 1, such as 1000 m / 1 km. Choose their direction so unwanted units cancel.
See the quantities change.
Predict before changing a value. The written explanation below remains available without JavaScript.
Convert the numerator and denominator
72 km/h × 1000 m/km ÷ 3600 s/h = 20 m/s. Dividing by 3.6 converts km/h to m/s; multiplying by 3.6 converts m/s to km/h. Understand the units before memorising a shortcut.
More units can mean a bigger numerical value
For the same speed, metres per second and kilometres per hour have different numbers. Predict whether the conversion is sensible. Do not round partway through a chain of conversions.
Khan Academy
Pause the explanation before a calculation. Predict the next step and explain which quantities are being compared.
Worked examples
A pump moves 2.5 L/min. Convert to mL/s.
- 2.5 L/min = 2500 mL/min.
- 2500 ÷ 60 = 125/3 mL/s.
- Approximately 41.67 mL/s; keep 125/3 for later exact calculations.
Try it before checking.
Convert 10 m/s to km/h.
A first hint
Convert metres to kilometres, then seconds to hours.
Compare your reasoning
10 × 3600 ÷ 1000 = 36 km/h.
Practise the skill.
Fresh questions · useful feedback
Build fluency, one decision at a time.
Work through eight questions. Two independent correct answers introduce a harder version; supported answers bring the next question back to the foundation. You can use hints at any time.
0 of 8 questions completed
This round saves on this device. It is practice, not a school mark.
Explain a little more.
Explain why multiplying by 1000 and dividing by 3600 gives the same result as dividing by 3.6.
Use this thinking in the If… project →