Multiple choice problems based on the confidence interval and correlation.

1) Find the linear correlation coefficient, r, between x and y. x: 0, 3, 3, 1, 4 y: 1, 7, 2, 5, 5
a)r=.333  
b)r=.749  
c)r=.974  
d)r=.497  

2)Express the confidence interval .600, .800 in the form p-hat plus and minus E.
a).8 plus and minus .2  
b).6 plus and minus .2  
c).6 plus and minus .3  
d).7 plus and minus .1  

3)Find the critical value. 99% confidence, sigma is unknown, population is normal, n=15.
a)2.977  
b)1.645  
c)1.965  
d)3.360  

4) Listed below are intervals (in minutes) between eruptions of the Old Faithful Geyser in Yellowstone National Park. Find the median. 98, 92, 95, 87, 96, 90, 65, 92, 95, 93, 98, 94
a)95.7  
b)100  
c)91.3  
d)93.5  

5) In a study of brand recognition 831 consumers knew of Campbell's soup and 18 did not. Use the results to estimate the probability that a randomly selected consumer will recognize Campbell's soup.
a).021  
b).979  
c).777  
d).999  

6) A test consists of multiple choice problems, each having 4 possible answers (a, b, c, d), 1 of which is correct. Assume you guess the answers to 6 such problems. Find the probability that the first 2 guesses are wrong and the last 4 guesses are correct.
1).00220  
2).10  
3).02200  
4).667  

7)The mean and standard deviation of a normal distribution is 100 and 15 respectively. Find the probability that a value is between 110 and 120.
a).1382  
b).1596  
c).9404  
d).2179  

8)Construct the confidence interval for the population proportion where n=1200, x=800, 99% confidence.
a).632, .702  
b).612, .712  
c).368, .902  
d).512, .602  

9)A dietician obtains the amounts of sugar from 100 centigrams in each of 10 different cereals, including Cheerios, Corn Flakes, Froot Loops, and 7 others. Those values are listed below. Find the mean. 3, 24, 30, 47, 43, 7, 47, 13, 44, 39
1)34.5  
2)47  
3)25  
4)29.7