baydong1989Lv1

25 Mar 2023

1.The Ice Chalet offers dozens of different beginning ice-skating classes. All of the class names are put into a bucket. The Monday night (ages 8 to 12) beginning ice-skating class was picked. In that class, there were 64 girls and 16 boys. Suppose that we are interested in the true proportion of girls (ages 8 to 12) in all beginning ice-skating classes at the Ice Chalet. Assume that the children in the selected class are a random sample of the population.

Define the random variable X.

a. the number of beginning ice-skating classes b. the time of the beginning ice-skating class     c. the number of girls, ages 8 to 12, in the beginning ice-skating class d. the number of boys, ages 8 to 12, in the beginning ice-skating class e. the total number of children in beginning ice-skating classes   2. A poll of 1,200 voters asked what the most significant issue was in the upcoming election. Sixty-five percent answered the economy. We are interested in the population proportion of voters who feel the economy is the most important.

What would happen to the confidence interval if the level of confidence were changed from 90% to 95%?   a. The confidence interval would become narrower because it would have to account for more variation. b. The confidence interval would become wider because it would have to account for more variation.     c. The confidence interval would become narrower because it would have to account for less variation. d. The confidence interval would become wider because it would have to account for less variation. e. There would be no change.