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How many bags of Hot cheetos are bought?. Nora Castro Jasmin Lopez Period 5 2011-2012. California Standards.
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How many bags of Hot cheetos are bought? Nora Castro Jasmin Lopez Period 5 2011-2012
California Standards • 17.0: students determine confidence intervals for a simple random sample from a normal distribution of data and determine the sample size required for a desire margine of error • 18.0: Students determine the p- value for a statistics for a simple random sample from a normal distribution
Hypothesis • We believe that the amount of cheetos bought per student is 2 bags.
Data Collection • We collected our data by using stratified sample method. We both split 40 students Nora asked 10 freshman and 10 sophomores Jasmin asked 10 juniors and 10 seniors about the amount of hot cheetos they each bought.
Data • Amount of cheetos bought (per student) • Nora: 0,1,2,2,2,1,3,0,2,3,1,1,1,1,4,2,1,1,2,1, • Jasmin: 1,1,2,5,4,2,2,3,2,1,6,2,1,1,1,1,2,1,2,1
Statistics • From our survey, the average amount of bags of cheetos bought per day is 1.80 bags with the sample standard deviation 1.24 bags.
Confidence Interval • 95% Confidence interval • Z-Interval • (1.415, 2.184) • We are 95 % confident that the amount of cheetos bought per day is between 1.415~ 2.184 bags.
Hypothesis Testing • Hypothesis Testing: Test at • Claim: we believe that the bags of chips bought is 2 bags per student. • p-value e=0.05 p-value:.3087<0.05 3. At 5% level of significance we failed to reject the claim. There is enough evidence to support our claim.
Error Analysis • Our sample mean is 1.8 bags, and the 95% confidence level of bags of cheetos bought per day is between 1.415 to 2.185 bags. The marginal error is about 0.385 bags. • Our sample error is due to possible underrepresentation of numbers of bags bought. We might need to take more sample do to the fact that not every students buy cheetos.
Conclusion • We hypothesized that Century students bought 2 bags of cheetos per day. In our survey of 10 freshman and10 sophomores and 10 juniors and 10 seniors a total of 40 students, we find the sample mean of 1.80 with a standard deviation of 1.24 bags. We conclude that the bags of chips bought is between 1.415~2.184 bags with 95% confidence. We test our initial hypothesis with 5% level of significance, and confirm our hypothesis is correct.