A contractor bought 12.6ft of sheet metal. He has used 3.7ft so far and has $142.40 worth of sheet metal remaining. The equation 12.6x-3.7x=142.40 represents how much sheet metal is remaining and the cost of the remaining amount. How much does sheet metal cost per square foot? Sheet Metal costs $__ per square foot

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?