Chapter 4

Problem Solving

Solve real-life time problems step by step: arrivals, durations and finishing times.

Solving time word problems

Word problems about time ask you to find a duration, a starting time or a finishing time. Read slowly and picture what happens. Use four simple steps: understand what is asked, plan whether you should add, subtract or count on, solve carefully one step at a time, then check that the answer makes sense. Underlining the given times and the question word often helps you choose the right step.

Key idea

Finish = start + duration. To find how long something lasts, count on from the start time to the finish time.

A worked problem

Worked example

A bus leaves at 0900 and the journey takes 2 hours 30 minutes. When does it arrive? Add the hours: 0900 + 2 hours = 1100. Then add the minutes: 1100 + 30 minutes = 1130. Check: from 0900 to 1130 is indeed 2 hours 30 minutes. So the bus arrives at 1130.

Remember

  • Add hours first, then minutes.
  • 60 minutes make 1 hour when minutes carry over.
  • Always check your answer against the question.
  • Write times clearly, and remember 60 minutes make one whole hour when minutes carry over.

Stuck on this topic? A verified JomKelas tutor can walk you through it.

Find a verified tutor