The A.C. Nielsen Company reported in the Nilsen Report on Television that the mean weekly television viewing time for children aged 2-6years is 24.85hours. Assume that the weekly television viewing times of such children are normally distributed with a standard deviation of 6.23hours and apply the empirical rule to fill in the blanks.

Part (a): Approximately role="math" localid="1652510212472" 68%of all such children watch between ___ and ___.

Part (b): Approximately role="math" localid="1652510208999" 95%of all such children watch between ___ and ___.

Part (c): Approximately 99.7%of all such children watch between ___ and ___.

Part (d): Draw graphs similar to those in Fig. 6.27on page 272to portray your results.

Short Answer

Expert verified

Part (a): Approximately 68%of all such children watch between 18.62hours and localid="1652511114283" 31.08hours.

Part (b): Approximately localid="1652511116226" 95%of all such children watch between localid="1652511123165" 12.39hours and localid="1652511127624" 37.31hours.

Part (c): Approximately localid="1652511118425" 99.7%of all such children watch between localid="1652511125683" 6.16hours and localid="1652511129723" 43.54hours.

Part (d): Graph of approximately localid="1652511120707" 68%of all such children,

Graph of approximately 95%of all such children,

Graph of approximately 99.7%of all such children,

Step by step solution

01

Part (a) Step 1. Given information.

Consider the given question,

The weekly television viewing time of children aged 2-6years is approximately normal with mean24.85hours and standard deviation6.23hours.

02

Part (a) Step 2. Determine the approximate of all such children within 68%.

By property of empirical rule, approximately 68%of values lie in the interval,

μ-σ,μ+σ=24.85-6.23,24.85+6.23=18.62,31.08

Thus, approximately 68%of all children watch between role="math" localid="1652510519610" 18.62,31.08hoursof TV per week.

03

Part (b) Step 1. Determine the approximate of all such children within 95%.

By property of empirical rule, approximately 95%of values lie in the interval,

μ-2σ,μ+2σ=24.85-26.23,24.85+26.23=12.39,37.31

Thus, approximately 95%of all children watch between12.39,37.31hours.

04

Part (c) Step 1. Determine the approximate of all such children within 99.7%.

By property of empirical rule, approximately 99.7%of values lie in the interval,

μ-3σ,μ+3σ=24.85-36.23,24.85+36.23=6.16,43.54

Thus, approximately 99.7%of all children watch between6.16,43.54hours.

05

Part (d) Step 1. Drawing graph representing approximately 68%,95%,99.7% of all children.

On drawing graph representing approximately 68%of all children,

On drawing graph representing approximately 95%of all children,

On drawing graph representing approximately 99.7%of all children,

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