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How many rods in this sample would you expect to have a length within $0.5\,\text{cm}$ of the mean length?
Mathematics 9709 · AS & A Level · The normal distribution
The normal distribution — practice question
A factory makes a specific kind of metal rod. These rods have lengths that are normally distributed with mean $25.2\,\text{cm}$ and standard deviation $0.4\,\text{cm}$. One random sample of $500$ of these rods is selected.
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