Unfortunately, a couple of the questions from the above worksheet have the incorrect link attached. Please find links for the correct explanation below:
2009A KS2 Q22 - https://www.youtube.com/watch?v=2sJ-cLHndsM&index=3&list=PLS3PH82bo0VBgaF4RCu1nFganpFTSFBqV
2012A KS2 Q22 - https://www.youtube.com/watch?v=o87CbHQKlq0
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