Question

A package has a mean mass of 340 g and a standard deviation of 1.5 g. Assuming that the masses are normally distributed, find the percent of packages with a mass below 336.7 g

Answer 1

The z-score for a weight of 336.7g is found as follows;

`z=(336.7-340)/(1.5)=-2.2`
The cumulative probability for a z-score of -2.2 can be found from a normal distribution table:
The cumulative probability for a z-score of -2.2 is 0.0139.
Therefore the answer is 1.39%.