1. Jada gathered data at her school among 7th and 8th graders to see if there was an association between grade level and playing sports. The table shows her data, but the
number of 8th graders who play sports is missing.
play sports
play
sports
don't play
sports
don't play sports
120
110
100
90
80
70
60
50
40
30
20
10
0
7th
graders
112
52
8th
graders
84
7th grade
8th grade
Jada found there was no evidence of an association between grade level and playing
sports. Which of these could be the number of 8th graders who play sports?
A. 248
B. 181
C. 144
D. 69

Abacteria population is tripling every hour. by what factor does the population change in 1/2 hour? select all that apply

(co 3) the times that customers spend in a book store are normally distributed with a mean of 39.5 minutes and a standard deviation of 9.4 minutes. a random sample of 25 customers has a mean of 36.1 minutes or less. would this outcome be considered unusual, so that the store should reconsider its displays? no, the probability of this outcome at 0.035, would be considered usual, so there is no problem yes, the probability of this outcome at 0.035, would be considered unusual, so the display should be redone no the probability of this outcome at 0.359 would be considered usual, so there is no problem yes, the probability of this outcome at 0.965 would be considered unusual, so the display should be redone

Arandom sample of n = 25 observations is taken from a n(µ, σ ) population. a 95% confidence interval for µ was calculated to be (42.16, 57.84). the researcher feels that this interval is too wide. you want to reduce the interval to a width at most 12 units. a) for a confidence level of 95%, calculate the smallest sample size needed. b) for a sample size fixed at n = 25, calculate the largest confidence level 100(1 − α)% needed.