1. Let  z be a normal random variable with mean 0 andstandard deviation 1. What is P(-2.25 <  z <-1.1)?
You are offered an investment opportunity. Its outcomes andprobabilities are presented in the following table.
| x | P(x) |
| -$1,000 | .40 |
| $0 | .20 |
| +$1,000 | .40
​ |
2. The mean of this distribution is _____________.
3. T/F. The probability that the complement of an event willoccur is given by P(E') = 1 - P(E)
True
False
4.
A recent survey of local cell phone retailers showed that of allcell phones sold five years ago, 64% had a camera, 28% had a musicplayer, and 22% had both. The probability that a cell phone soldfive years ago did not have either a camera or a music playeris
5.
The sample standard deviation is related to the sample variancethrough what functional form?
| | Square root |
| | Linear |
| | Exponential |
| | Logarithm |
6.
A large industrial firm allows a discount on any invoice that ispaid within 30 days. Of all invoices, 10% receive the discount. Ina company audit, 10 invoices are sampled at random. The binomialprobability that fewer than 3 of the 10 sampled invoices receivethe discount is approximately_______________.
7.
Suppose x is a normal random variable with mean 60 and standarddeviation 2. A z score was calculated for a number, and the z scoreis 3.4. What is the inverse normal calculation of x?
