Free interactive maths lesson for primary children

Time Difference

Find how much time passes between a start time and an end time. Learn two methods step by step, then practise. This public lesson is available without an account.

Method 1: the timeline

Count forward on a timeline: jump to the next hour, then whole hours, then the remaining minutes. Add the jumps to find the duration.

Method 2: direct subtraction

Write End minus Start in hours and minutes columns. When there are not enough minutes, exchange 1 hour for 60 minutes, because 1 hour = 60 minutes, not 100. Afternoon times are changed to 24-hour time first.