was wondering, in the probability exam will we get more/better marks if we use the formula, Z = x-m / standard deviation? or is ok just to skip straight to the part where we put it into the calculator?
Thanks, Sam 
Hi sam
You don’t need to show any working for questions that give you the mean and standard deviation if you are using a graphics calculator. Some questions will be set up in such a way that you HAVE to use the formula to solve them (eg finding the mean or standard deviation). These are usually merit or excellence questions.
MT4
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