AP Statistics Sampling Distributions

Portly Polls asked 149 fourth year college students on average, how much they spent for lunch. According to the colleges, the average amount they spent for lunch is N(30,10). Portly Polls got less than $30.4 on average. How likely is this result?

• 84.02%

• 68.79%

• 165.5%

• 58.37%

Perilous Polls asked 62 third year college students on average, how much they spent for lunch. According to the colleges, the average amount they spent for lunch is N(35,8). What is the probability that Perilous Polls' random sample will give a result within 0.01 of the true value?

• 48.8%

• 50.4%

• 49.6%

• 0.8%

Random samples of size 11 are selected from a population with mean 33 and standard deviation 6. What is the mean and standard deviation of the sampling distribution?

• 
• 
• 
• 

Perilous Polls asked 36 first year college students on average, how much they spent for lunch. According to the colleges, the average amount they spent for lunch is N(40,6). What is the probability that Perilous Polls' random sample will give a result within 0.02 of the true value?

• 49.2%

• 50.8%

• 1.6%

• 47.6%

Perilous Polls asked 145 second year college students on average, how many credits they have taken. According to the colleges, the average number of credits they have taken is N(25,1). Perilous Polls got less than 24.95 on average. How likely is this result?

• 248.1%

• 17.01%

• 42.66%

• 27.43%

Portly Polls asked 41 second year college students on average, how much they spent for lunch. According to the colleges, the average amount they spent for lunch is N(20,1). Portly Polls got less than $19.6 on average. How likely is this result?

• 9.9%

• 5172%

• 15.75%

• 0.52%

How can you check to see if your sample of size n is large enough to apply the Central Limit Theorem?

• n ≤ 10

• n ≤ 30

• n ≥ 10

• n ≥ 30

Polly's Polls asked 100 third year college students on average, how much they spent for lunch. According to the colleges, the average amount they spent for lunch has a mean of 20, and standard distribution of 7. What is the probability that Polly's Polls' random sample will give a result within 0.02 of the true value?

• 51.2%

• 46.4%

• 48.8%

• 2.40%

What does σ² equal?

• n(p-1)/n

• σ²/n

• n(p-1)/p

• p(1-p)/n