一道數(shù)學(xué)概率問題 英文題目哦
(a) In the national lottery, you identify 6 balls from a set of 49 balls. Then 6 balls are selected at random from the 49 balls and you get a prize if at least 3 of these match the balls you identified. (Ignoring the bonus ball for now)
---What is the probability that you get a prize of some sort?
(b) actually it is more complicated; after the 5 balls are selected at random, a sixth “bonus” ball is selected at random and you get a special kind of prize if, of the six balls you identified, 5 were in the selected group of six and the sixth is the bonus ball (as well as all the prizes for matching 3 or more of the first six balls)
---What is the probability you get a special kind of prize just described?
---Keeping this in mind, what is the probability that you get a prize of some sort?