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What percent of babies have birthweight between 8.2 and 9.2 pounds? Show work.

Students tested a six-sided die to see if it was fair. A fair die means that each of the six numbers has the same probability of being rolled. The students rolled the die 100 times. Then they conducted a chi-square goodness-of-fit test with a level of significance of 0.05. They calculated the p-value to be 0.045. Which of the following is the most appropriate conclusion?

A survey was administered to 100 randomly chosen students. The students were asked whether or not they had travelled outside of the United States (call this variable “travel”) and whether or not they liked spicy food (call this variable “spicy food preference”). What would be the appropriate hypothesis statements if you decided to conduct a chi‐square test of independence for these two variables?

Students at a local college wanted to know whether there is a relationship between natural hair color and eye color. They conducted a test to study this issue.  If, after analyzing their data, they find a significant χ2{“version”:”1.1″,”math”:”χ2″} value and therefore a low p-value, this would suggest that:

Using the output information, what can you conclude about the difference of ratings in the taste between two brands of cola?

The 95% confidence interval was estimated to be (0.752, 2.0478). Based on the confidence interval, which of the following is a valid conclusion?

Using the margin of error given in the previous problem, which of the following is the 99% confidence interval for the true difference between the 2016 and 2021 groups?  Recall that the sample proportion from 2016 was 57% and the sample proportion in 2021 was 60%.  Let p16 represent the true proportion in 2016 and p21 represent the true proportion in 2021. You should be finding the confidence interval for p16 – p21 .

It is assumed that the sampling distribution for the difference between the two sample proportions (from the group sampled in 2016 and the group sampled in 2021) is approximately normal. Which of the following explanations provides the best reason why?

Which of the following represents the accurate null hypothesis for testing to see if there is a difference between the two population proportions?

Suppose you and your friend make a bet before the 1200 rolls take place. You agree that you will pay your friend $1 for every roll that comes up a 3 or a 4, and your friend will pay you $3 for every roll that comes up a 5. No money will be exchanged for rolls that come up 1, 2, or 6. Who do you expect will make more money on this deal? How much more money will that person make?