Midland Electronics is advertising that everything in their store is 10% off. If p
represents the original price of an item in their store, then the sale price of the item can be represented by the expression
p
−
0.1
p
.

A. Write an equivalent expression to represent the sale price of the item.

B. Using complete sentences, describe how the sale price can be found in two different ways.

In a test for esp (extrasensory perception), a subject is told that cards only the experimenter can see contain either a star, a circle, a wave, or a square. as the experimenter looks at each of 20 cards in turn, the subject names the shape on the card. a subject who is just guessing has probability 0.25 of guessing correctly on each card. a. the count of correct guesses in 20 cards has a binomial distribution. what are n and p? b. what is the mean number of correct guesses in 20 cards for subjects who are just guessing? c. what is the probability of exactly 5 correct guesses in 20 cards if a subject is just guessing?