PA-4 / Lesson 4
This page lists extra materials and problems for anyone who's finished everything else in this lesson. They're tougher, but still doable — especially if you found the main materials easy.
Problem 1.
You are taking out candies one by one from a jar that has 10 red candies, 20 blue candies, and 30 green candies in it. What is the probability that there are at least 1 blue candy and 1 green candy left in the jar when you have taken out all the red candies?
Problem 2.
Adarsh is going to make 100 shots at the basket. The first time he scored, but the second time he missed. The probability of scoring each time is equal to the percentage of successful shots in all previous attempts. What is the probability that he will score exactly 50 shots?
Problem 3.
In a queue, $n$ people of different heights are lined up back to back. Nastya stands in front of them and looks at the queue. Taller people block shorter people, making them invisible. What is the expected number of people that Nastya can see?