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Which of the following statements would be a correct conclusion?   Hint: I can’t 

Weights of newborn babies are normally distributed with a mean of 7.5 lb and a standard deviation of 1.25 lb. A newborn whose weight is in the lowest 4% of the population is classified as low birth weight. Find the cutoff for the lowest 4% of birth weights. Hints: Find the Z score so that the area to the left of the Z score is .04 2nd -> Vars-> INVNORM(Area,

Studies indicate that 12% of American adults have diabetes. If 10 adult Americans are selected at random, what is the probability that at least four have diabetes? Hints: It’s a binomial probability distribution 🙂  1-binomcdf(10,.12,3)  

2.1 Explain what a ‘hunter-gatherer’ is. (2)

Calculate the P-value. Hint: Stats -> Test->  1PropZTest 

The National Health Statistics Reports published in 2008 reported the following weights for randomly selected samples of one year old girls and one year old boys. The means and standard deviations are in pounds. Group Girls Boys Mean 24.1 24.5 Standard Deviation 4.3 4.1 Sample Size 328 300 Construct and interpret a 96% confidence interval for the difference between the mean weights. Hints: Since you’re dealing with 2 independent samples, to construct the confidence interval STATS->TESTS-> 2SampleTinterval . (+,+) Positive difference ; (-,-) Negative difference ; (-,+) there’s not a significant difference between the variables 

Myers Corporation has the following data related to direct materials costs for November: actual costs for 4,700 pounds of material were $5.30 per pound and standard costs for 4,420 pounds of material are $6.30 per pound. What is the direct materials price variance?

The number of M&Ms in a bag were counted and recorded. The data are summarized in the frequency distribution below. X 52-53 54-55 56-57 58-59 60-61 f 1 7 12 7 2 Calculate the relative frequency of the 5th class. Hint: Relative Frequency = Frequency / sample size 

Jaxson Corporation has the following data related to direct labor costs for September: actual costs are 10,200 hours at $15.75 per hour and standard costs are 10,800 hours at $15.50 per hour. What is the direct labor time(efficiency) variance?

In a survey of 15,200 college students, 5335 said they had smoked in the last 30 days. In another survey of 12,900 college students taken four years later, 3444 said they had smoked in the last 30 days. At α = 0.10, can you support the claim that the proportion of college students who said they had smoked in the last 30 days has changed? State the null and alternative hypotheses if the earlier sample is the first sample and the later sample is the second sample. Hints: You’re dealing with two independent sample PROPORTIONS . *  changed/different (2 tailed test)