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Given that $1\%$ of the tea packets are underweight, find $\sigma$.
Mathematics 9709 · AS & A Level · Continuous random variables
Continuous random variables — practice question
Tea packets are labelled as containing 250 g. The true mass of tea in a packet follows a normal distribution with mean 260 g and standard deviation $\sigma$ g. Any packet whose mass is below 250 g is described as ‘underweight’.
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