The mean age of participants in your study is 20.1 years with a standard deviation of 2.7 years. As you write up your results, you realize that what matters is the ages of the participants two years ago when the event happened, not their ages now. You decide to subtract 2 from each of your participants’ ages. After you subtract 2 years, the mean age in your sample is18.1 years. The new standard deviation of the ages in your sample is years.

Mariah is randomly choosing three books to read from the following: 5 mysteries, 7 biographies, and 8 science fiction novels. which of these statements are true? check all that apply. there are 20c3 possible ways to choose three books to read. there are 5c3 possible ways to choose three mysteries to read. there are 15c3 possible ways to choose three books that are not all mysteries. the probability that mariah will choose 3 mysteries can be expressed as . the probability that mariah will not choose all mysteries can be expressed as 1 −