it is generally believed that nearsightness affects about 15% of al children. a local elementary school registered 120 incoming kindergarteners.
Note that this scenario is talking about a sampling distribution sincer this school is a sample size 120, therefopre, you will need to calculate the standard deviation using a formula before using the normalcdf aqnd invNorm commands.
(a) what is the mean of the sampling distribution of all samples like this
(b) what is the standard deviation of the sampling distributrion of all samples like this
(c) what is the probability that less tahn 10%of the incoming kindergarteneres are nearsighted?
(d) if this school measutre at the 80th percentile for all incoming kindergarten classes of size 120, what proportion of incoming kindergarteners are nearsighted?