an ice skating rink charges $9 per session to skate and an additional $3 to rent skates. if someone goes to ice rink 15 times in three months and spends $165 how many times did they forget their skates and need to rent them?

Prove that the sum of two consecutive exponents of the number 5 is divisible by 30.if two consecutive exponents are 5n and 5n + 1, then their sum can be written as 30.

Suppose a gym membership has an initial enrollment fee of $75 and then a fee of $29 a month. which equation models the cost, c, of the gym membership for m months?

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?