The popularity of computer, video, online, and virtual reality games has raised concerns about their ability to negatively impact youth. The data in this exercise are based on a recent survey of 14 ‑ to 18 ‑year‑olds in Connecticut high schools. Assume the table displays the grade distributions of boys who have and have not played video games. Grade Average A's and B's C's D's and F's Played games 730 444 190 Never played games 214 137 87 Give the conditional distribution of the grades of those who have played games. (Enter your answers rounded to two decimal places.)

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general 10 months ago 5550

Geoff has been running a restaurant in the city for many years. He knows from experience that the proportion of customers that leave tips at this restaurant is 0.56. Geoff has recently opened a restaurant in a suburban area. It seems that tipping habits are different in the suburbs: Geoff believes that the proportion of customers that tip at his new restaurant (p) may be different to 0.56. He conducts a hypothesis test to find out. The null and alternative hypotheses are: H0: p = 0.56 Ha: p ≠ 0.56 Geoff takes a random sample of 113 customers and notes whether or not they leave a tip. In this sample, the proportion of people that leave a tip is 0.60. a)Calculate the test statistic (z). Give your answer to 2 decimal places. z = 0.857 b)Calculate the P-value. Give your answer as a decimal to 4 decimal places. P-value = 0.3898

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general 10 months ago 7379

A group consists of seven men and seven women. Four people are selected to attend a conference.a. In how many ways can four people be selected from this group of fourteen​?b. In how many ways can four women be selected from the seven ​women?c. Find the probability that the selected group will consist of all women.a. The number of ways to select four people from the group of fourteen is nothing.b. The number of ways to select four women from the group of seven women is nothing.c. The probability is nothing.​(Type an integer or a simplified​ fraction.)

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general 10 months ago 1761

The label on 1-gallon can of paint states that the amount of paint in the can Is sufficient to paint at least 400 square feet (on average). Suppose the amount of coverage Is approximately normally distributed, and the overall standard deviation of the amount of coverage is 27 square feet. A random sample of 16 cans yields the sample mean amount of coverage of 390 square feet. Test the claim on the label at a 5% level of significance. Enter the test statistic in the first box and your decision in the second box (0 if you reject and 1 if you don't (i.e if you accept) Find the p value of the test in part (a)

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general 10 months ago 8038