A sales consultant for Herron Pharmaceuticals wished to confirm that their packet of 24 paracetamol tablets was cheaper at the retail level than their rival product. The sales consultant collected price data from two independent samples, of size 27 for Herron and 18 for the rival company. These yielded an average and variance for the retail price of Herron's product of 399 cents and 76 cents squared respectively, and 402 cents and 61 cents squared for the rival. Under the usual assumptions, determine a 95% confidence interval for the price difference (use Herron minus rival) stating only the upper limit of the interval in cents (round to the nearest whole number).

(c)For the mileage values in this sample, 36.4 thousand miles is more extreme than 25.3 thousand miles is, that is, 36.4 is farther from the sample mean mileage than 25.3 is. How would the 90% confidence interval for the mean used selling price when the mileage is 36.4 thousand miles compare to the 90% confidence interval for the mean used selling price when the mileage is 25.3 thousand miles? The intervals would be identical. The interval computed from a mileage of 36.4 thousand miles would be narrower and have a different center. The interval computed from a mileage of 36.4 thousand miles would be wider but have the same center. The interval computed from a mileage of 36.4 thousand miles would be narrower but have the same center. The interval computed from a mileage of 36.4 thousand miles would be wider and have a different center.

These are the means and standard deviations for samples of prices from two different brands of shoes.Brand A Brand BMean: $50 Mean: $40Standard deviation: $5 Standard deviation: $8Select the two true statements.A.Brand A has a lower average price than brand B.B.Brand A's prices are less spread out than brand B's prices.C.Brand A's prices are more spread out than brand B's prices.D.Brand A has a higher average price than brand B.SUBMITarrow_backPREVIOUS

Continuous Probability DistributionsNow, let’s say that QC decides to sample one more tablet. This time, it selects a tablet from Batch Y4. Based on previous knowledge, you know that Batch Y4 has a mean paracetamol level of 505 mg, and its standard deviation is 25 mg. This time, QC wants to check both the upper limit and the lower limit for the paracetamol level.What is the probability that the tablet selected by QC has a paracetamol level between 450 mg and 550 mg?

A representative of a consumer advocacy group randomly selects 50 bags of a certain brand of chips and determines the net weight of each. He finds the mean of these selected bags to be 395 grams and the standard deviation to be 6.8 grams. Calculate a 90% confidence interval for the true mean of weight of chips. What is the lower limit of the interval?

In Exercise 2 of Tutorial 4, first we developed a confidence interval for the difference between the mean ages of purchasers and non-purchasers of a particular brand of toothpaste (part a), and then performed a t-test to see whether there was sufficient evidence to conclude that there was a difference in the mean age of purchasers and non-purchasers (part b). Based on the sample variances, in both cases we assumed that the two unknown population variances are different. Let’s check now whether this assumption is supported by the data.Namely, using the same data,a) Estimate the ratio of the two population variances with 95% confidence.b) Can we conclude at the 5% significance level that the population variances differ? What do you conclude if the significance level is increased to 10%?In parts (a) and (b) alike, do the calculations both manually and with R.