Thank you so much for spotting the error - that should all be fixed now.
Posted on 6th November 2019
I think this is a great resource but I should note there is an error in the answers to step 5 & 6.
After step 4 you have 3 red and 15 yellow, step 5 states, add 2 red and 2 yellow, this gives a ratio of 5:17 not 12:17 as given in the answers.
Posted on 12th October 2019
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