15. The purpose of statistical inference is to provide information about the mean of the sample based upon the mean of the population population based upon information contained in the sample sample based upon information contained in the population population based upon information contained in the population

3. The table below illustrates the number of visitors to Museum Fantastic over the last 100 days': No. of Visitors No. of Days 21 - 40 22 41 - 60 4y+2 61 - 80 26 2y-4 81 - 100 (a) Find the value of mean, mode and standard deviation for this dataset. (b) By comparing the values of mean and mode, what can you say about the skewness of this data? Justify your answer with the Pearson's measure of skewness. (c) The mean and standard deviation for the number of visitors at Museum Awesome over the same period of time are 53 and 21.5 respectively. Determine which museum has relatively dispersed number of more Justify your answer. visitors.

The mean output of solar cells of three types is measured six times under random light intensity over a period of 5 minutes, yielding the results shown. Research question: Is the mean solar cell output the same for all cell types?

Suppose the mean miles per gallon for a sample of 70,000 new cars and light trucks sold in the United States in 2017 differs from the population mean  by more than one gallon. How would you interpret this result?