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Use an approximation to calculate the chance that more than $40$ of these components are faulty.
Mathematics 9709 · AS & A Level · The normal distribution
The normal distribution — practice question
A factory makes one particular kind of electrical component. It is known that $15\%$ of the components made are faulty. A random sample of $200$ components is selected.
Worked solution & mark scheme
This 5-mark question has a full step-by-step worked solution and mark scheme. One marking point: “The mean and variance are found correctly as $\mu=200\times 0.15=30$ and $\sigma^2=200\times 0.15\times 0.85=25.5$.” …
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