(a)[4]
What number of these 350 bars would you expect to lie between 148 g and 160 g?
(b)[5]
Determine the values of $\mu$ and $\sigma$.
Mathematics 9709 · AS & A Level · The normal distribution
The normal distribution — practice question
A chocolate-bar factory makes chocolate bars. Their weights are normally distributed with mean 155 g and standard deviation 6 g. One random sample of 350 bars is selected. A second chocolate-bar factory also makes chocolate bars. Their weights are normally distributed with mean $\mu$ g and standard deviation $\sigma$ g. Tests indicate that 8% of the bars weigh more than 114.0 g and 20% weigh less than 99.5 g.