Complete the following problems: Explain the solution step by step: 1. Suppose t
ID: 3051348 • Letter: C
Question
Complete the following problems: Explain the solution step by step: 1. Suppose that a class contains 15 boys and 25 girls, and that 8 students are to be selected at random for a special assignment. Find the probability that exactly 3 boys will be selected 2. Suppose that a class contains 15 boys and 25 girls, and that 8 students are to be selected at random for a special assignment. Find the probability that at least 3 boys and at least 4 girls wil be selected 3. Assume you have 12 books 3 yellow, 4 red and 5 blue and you want to arrange them on a bookshelf. In how many ways can we arrange the books so all red books are at the right side of the shelf? 4. Assume you have 12 books 3 yellow, 4 red and 5 blue and you want to arrange them on a bookshelf. In how many ways can we arrange the books if we want all Blue books on the shelf and we can only fit 10 on the shelf?Explanation / Answer
Solution:
1) Ways to choose 8 students out of 40 = 40c8 = 40!/(8!*32!) = 76904685
Ways to choose 3 boys out of 15 AND ways to choose 5 girls out of 25
= 15c3 * 25c5 = 15!/(3!*12!) * 25!/(5!*20!)
= 455 * 53130 = 24174150
probability that exactly 3 boys will be selected = 24174150/76904685 = 0.314339107