Time and speed problems are almost always solved by the same triangle. If your child knows it, these questions become some of the easiest marks on the paper.
The triangle
Distance = Speed × Time. Cover the value you want, and the other two tell you what to do. Want distance? Speed times time. Want time? Distance divided by speed.
Watch the units
If speed is in km/h but the time is in minutes, convert one of them first. Practice now on speed-distance-time questions to drill the unit conversions.
Clock arithmetic
11+ questions often involve a journey "starting at 09:45, lasting 2 hours 35 minutes". Break it: 09:45 + 2h = 11:45; 11:45 + 35m = 12:20. Don't try to add in one go.