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Succeed with maths: part 1

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# 5.1 Subtracting one number from another

As with addition, you may feel comfortable already with how to perform subtraction on paper. You may have also learned a different method to the one shown here and if this works for you it’s fine to continue with your method. Here’s a quick overview in case you feel that you need a reminder.

Write out the calculation so that the decimal points and the corresponding columns line up, making sure the number you are subtracting is on the bottom. Then, subtract the bottom number from the top number in each column, starting from the right. Remember, if you need to borrow from the next column, you need to change the value in that column. Figure 15 below describes how you can do this. You will only need to do this if you don’t have enough in one column to perform the subtraction.

Figure 15 Subtracting one number from another

Now it’s time to put your knowledge to use in an activity using addition and subtraction when dealing with the slightly trickier situation of time.

## Activity 4 Time, addition and subtraction

Timing: Allow approximately 10 minutes

Imagine you are travelling by train to attend a very important meeting. The train is leaving at 9:35 a.m. and arriving at 11:10 a.m. The ticket costs £48.30 but you have a refund voucher for £15.75, following the cancellation of a train on an earlier journey. How long will the journey take, and how much money will you have to pay for the ticket if you use the entire refund voucher?

Remember, if you need a hint, click on ‘Reveal comment’.

### Comment

Start by taking out and listing all the information from the question – this should help to make the problem clearer.