027 - Use each number once
Click on 'Download Document' at the bottom of this page. Once you have done that, open up the file.
Look at and try a question, then click on the youtube link to see a video on how to answer the question correctly, and see if you got it right!
Tip: If you have a printer at home, you could print the questions page and write your answer on the sheet before you watch the youtube video for each question.