a pro baseball player has a 30% chance of getting a hit on any at-bat. he swings 12 times. whats the probability that he doesnt get a hit?
If he has a 30% chance of getting a hit, then what is the probability that he does *not* get a hit? 70%. This problem is asking you the probability that that event takes place 12 times in a row. Repeated events like that require you to multiply the probability each time, so we get 0.70^12. Similarly, the odds of getting a hit all 12 times would be 0.30^12. Both are incredibly small numbers if you work them out, which reinforces the idea that the vast majority of the time you'll end up in the middle.