A Random Sample of 60 Students in the Business Statistics

question 88

Essay

A random sample of 60 students in the business statistics course answered a survey on the average number of hours they spent on statistics each week.Unfortunately,the original data were lost and all that remains is the frequency table below.From these data,calculate the estimated sample standard deviation. $\begin{array}{cccccc}\text { Class } & \text { Hrs } & \text { N } & \text { Midpt } & \text { fM } \\1 & 0-3 & 18 & 1.5 & 27 \\2 & 4-7 & 16 & 5.5 & 88 \\3 & 8-11 & 14 & 9.5 & 133 \\4 & 12-15 & 10 & 13.5 & 135 \\5 & 16-19 &\underline { 2} & 17.5 & \underline {35}\\&&60&&418\\\end{array}$

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Definitions:

Immunization

The process by which an individual becomes protected against a disease, typically through vaccination.

Cow Pox

A disease of cows caused by the cowpox virus, which is related to the variola virus of smallpox. Historically important as the basis for the first smallpox vaccine developed by Edward Jenner.

Lymphocytes

A type of white blood cell essential for immune responses, playing a crucial role in recognizing and fighting off pathogens.

Secondary Immune Response

The rapid production of antibodies induced by a second exposure to an antigen several days, weeks, or even months after the initial exposure.