A certain company makes many, many different puzzles, all of the same difficultly level. The times it takes Jack to assemble such puzzles are normally distributed with mean 475 minutes and standard deviation 30 minutes. Sam's times are normally distributed with mean 500 minutes and standard deviation 20 minutes. Find the following probabilities. Answers to four places after the decimal, using normal charts. Each are given a copy of the same puzzle. Find the probability that Jack will finish before Sam: Find the probability that Jack's average time on 4 puzzles is less than Sam's average time on 4 puzzles:

L9Q1.The following table shows the mode of travel and the probability of risk. Choose the best mode of travel for a safe trip.

June is a student taking a statistics course. Unfortunately, June is not a diligent student.  She does not read the textbook before or after class, does not do homework, and regularly misses class.  She intends to rely on luck to pass the next quiz.  The quiz consists of 10 multiple-choice question.  Each question has five possible answers.  Only one of the answers is correct, so the probability of choosing the correct answer is 0.20.  June plans to guess the answer to each question independently.  Let �  be the number of correct answers on June’s quiz.   What is the standard deviation of correct answers for June? Group of answer choices 8 2 1.26 1.14 None of These

Suppose 58% of the children in a school are girls.   If a sample of 425 children is selected, what is the probability that the sample proportion of girls will be greater than 63%? Round your answer to four decimal places.