Time, mass, speed

1 tonne = 1000 kg and 1 kg = 1000 g, so 1 tonne = 1 000 000 g. Multiply tonnes by 1000 for kilograms or by 1 000 000 for grams.

The journey from 06:33 to 10:33 lasts 4 hours. Average speed = distance ÷ time, so 260 ÷ 4 = 65 km/h.

Distance = speed × time. Speed in km/h and time in hours give distance in kilometres. For example, 60 km/h × 3 h = 180 km.

Find time by dividing distance by speed, but first make the measurement units compatible.

1. Divide the distance in metres by 1000 to convert it to kilometres.
2. Divide the distance in kilometres by the speed in kilometres per hour. This gives time in hours.
3. Multiply the time in hours by 60 to convert it to minutes.
4. Round the result to the nearest whole number.

Formula: time in minutes = (distance in metres ÷ 1000) ÷ speed × 60.

One hour contains 60 minutes. Divide the minutes by 60 to obtain hours. For example, 180 min = 180 ÷ 60 = 3 h.

One hour contains 60 minutes. Multiply the hours by 60 and add the remaining minutes: total minutes = h × 60 + min.

One hour contains 60 minutes. Divide the minutes by 60 to obtain hours. For example, 180 min = 180 ÷ 60 = 3 h.

One hour contains 60 minutes. Multiply the hours by 60 and add the remaining minutes: total minutes = h × 60 + min.

1 kg = 1000 g. Multiply the kilograms by 1000. For example, 6 kg = 6000 g.

Recall that a kilometre contains 1000 metres and an hour contains 3600 seconds. Multiply the speed in kilometres per hour by 1000 and divide by 3600 to obtain metres per second. Round only the final result: if the tenths digit is 5 or more, round up; otherwise round down.