A Test of Writing Ability Is Given to a Random $\overline { \mathrm { d } }$

question 27

Multiple Choice

A test of writing ability is given to a random sample of students before and after they completed a formal writing course.The results are given below.Construct a 99% confidence interval for the mean difference between the before and after scores if $\overline { \mathrm { d } }$ (before - after) = 2.0 and sd =2.6457 $\text { Before } 70\quad80\quad92\quad99\quad93\quad97\quad76\quad63\quad68\quad71\quad74$ After 69 79 90 96 91 95 75 64 62 64 76

• A)(-0.2,4.2)
• B)(-0.1,4.1)
• C)(-13.6,17.6)
• D)(1.2,2.8)
• E)(-0.5,4.5)

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Stockholders' Equity

The residual interest in the assets of an entity after deducting liabilities, representing ownership interest held by stockholders.

Noncontrolling Interest

The portion of equity in a subsidiary not owned by the parent company, reflecting the interests of outside investors.

Subsidiary's Net Income

The amount of profit remaining after all expenses, including taxes and operating costs, have been subtracted from total revenue, specific to a company that is controlled by another entity.