# Math Help - Proportions

1. ## Probabilities

Any help will do. Just cant seem to make any sense of this question.
A jam manufacturer produces a pack consisting of 8 assorted pots of different flavours, each normally weighing 50g. In practice the actual weight of each pot is independently normally distributed with mean 52g and standard deviation 1.10g. What is the probability of one or more pots in the pack weighing less than 50g?

2. Originally Posted by Pink Lady
Any help will do. Just cant seem to make any sense of this question.
A jam manufacturer produces a pack consisting of 8 assorted pots of different flavours, each normally weighing 50g. In practice the actual weight of each pot is independently normally distributed with mean 52g and standard deviation 1.10g. What is the probability of one or more pots in the pack weighing less than 50g?
Let X be the random variable weight of pot (in grams).

X ~ Normal $(\mu = 52, \sigma = 1.10)$.

Calculate p = Pr(X < 50) in the usual way.

Let Y be the random variable number of pots weighing less than 50 g.

Y ~ Binomial(n = 8, p = value found above)

Calculate $\Pr(Y \geq 1) = 1 - \Pr(Y = 0)$.