Question

A company produces packets of soap powder labeled "giant size 32 ounces." the actual weight of soap powder in a box has a normal distribution, with a mean of 33 oz. And a standard deviation of 0.7 oz. What proportion of packets are underweight (i.E., weigh less than 32 oz.)?

Answer 1

Find the area under the standard normal curve from negative infinity to 32 oz.

If you have a calculator with statistical functions, such as the old TI 83Plus I use, then an example of the command to use here would be:

normalcdf(-1000,32, 33,0.7).

Result: 0.077

Approx. 7.7% of packages would be underweight.