Marice mows the lawns on saturday. last week it took him 5 1/2 hours to finish. this week it took only 5 hours. how many times longer did it take last week than this week?

Cot(90° − x) = 1 the value of x that satisfies this equation is °. a. 60 b. 135 c. 225 d. 315

Math each whole number with a rational, exponential expression

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?