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Topic

Time, Distance and Speed

Time and travel questions use timetables, journey durations, speed, distance, time, and average speed in practical planning contexts.

Topic explanation

Keep times in the same format. If speed is in km/h, change minutes into hours before calculating.

Minutes are converted to hours by dividing by 60. For example, 2 hours 15 minutes is 2.25 hours, not 2.15 hours.

Timetable questions often include waiting time or a latest arrival time. Answer the actual question, not just the first calculation.

Average speed describes a whole journey. It can include waiting or slower sections if those are part of the total time given.

Quick methods

Duration
Count from the start time to the finish time.
Finish time
Add the journey time to the start time.
Distance
Distance = speed × time
Time
Time = distance ÷ speed
Average speed
Average speed = total distance divided by total time

Worked examples

Average speed with decimal hours

A car travels 126 miles in 2 hours 15 minutes. Calculate the average speed.

  1. Convert 2 hours 15 minutes to 2.25 hours.
  2. Average speed = distance ÷ time
  3. 126 ÷ 2.25 = 56

Answer: The average speed is 56 mph.

Watch out: Remember that 2 hours 15 minutes is 2.25 hours, not 2.15 hours.

Find time from speed and distance

A cyclist travels 18 km at an average speed of 12 km/h. How long does the journey take?

  1. Time = distance ÷ speed
  2. 18 ÷ 12 = 1.5 hours
  3. 1.5 hours is 1 hour 30 minutes.

So: The journey takes 1 hour 30 minutes.

Watch out: A decimal hour is not minutes. 0.5 hours is 30 minutes.

Timetable and speed

A train leaves at 09:48 and arrives at 11:06. It travels 96 km. Find the average speed.

  1. Journey time from 09:48 to 11:06 is 1 hour 18 minutes.
  2. 18 minutes = 18 ÷ 60 = 0.3 hours, so total time is 1.3 hours
  3. Average speed = 96 ÷ 1.3 = 73.8 km/h to 1 decimal place

Final step: The average speed is about 73.8 km/h.

Watch out: Convert minutes by dividing by 60 before using km/h

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