stats ch 4.4

You are getting a line-up ready for a school kickball game. You have 5 girls and 5 boys. The rules state each child must kick the same number of times and alternate girl-boy or boy-girl. How many ways can a line-up be made for one round of kicking?

(5!x5!)x2=28800

You are ordering a hamburger and can get up to 7 toppings, but each topping can only be used once. You tell the cashier to surprise you with the toppings you get. What is the probability that you get 2 toppings?

21/128 (see notes for example)

A doctor visits her patients during morning rounds. In how many ways can the doctor visit 8 patients during the morning rounds?

8!=40320

permuatation

a selection of objects from a group where the arrangement is specific.

combination

a selection of objects from a group without regard to their arrangement.

7 cards are drawn from a standard deck of 52 playing cards. How many different 7-card hands are possible if the drawing is done without replacement?

133784560 (combo)