Symbols you can use to copy and paste for problems:

x

When typing in equations/hypothesis using any symbols do NOT enter any spaces!!

Ex: if entering the confidence interval formula it should look like:

xz*(/n)

not

x z* ( / n)

The average baby at birth weighs 6.2 lbs with a standard deviation of 0.48lbs. In a SRS of n=50 newborn twins the average weight was found to be 5.68 lbs. Is there statistically significant evidence at the .05 level that babies born as a twin weigh less than average?

(don't use spaces in your answers!!! The first one is done for you.)

Ho: =6.2 Ha:

The test statistic is z=

with the following associated p-value:

So the conclusion of this statistical test is:

we (reject/fail to reject) the Ho.

There (is/is not) statistical evidence at the .05 level that (you can copy and paste the wording used in the statistical question above).

Compute the confidence interval for this sample:

State a 95% confidence interval for the mean baby weight of a child born as a twin:

We are % confident that is between lbs. and lbs.