All current-carrying wires produce electromagnetic (EM) radiation, including the electrical wiring running into, through, and out of our homes. High-frequency EM radiation is thought to be a cause of cancer. The lower frequencies associated with household current are generally assumed to be harmless. To investigate the relationship between current configuration and type of cancer, researchers visited the addresses of a random sample of children who had died of some form of cancer (leukemia, lymphoma, or some other type) and classified the wiring configuration outside the dwelling as either a high-current configuration (HCC) or a low-current configuration (LCC). Here are the data:

Computer software was used to analyze the data. The output included the value X2=0.435

Which of the following is the expected count of cases with lymphoma in homes with an HCC?

a. 79×31215

b. 10×21215

c. 79×3110

d. 136×31215

e. None of these

Short Answer

Expert verified

Option(a) is the expected count of cases with lymphoma in homes with an HCC.

Step by step solution

01

Given information

We need to find the expected count of cases with lymphoma in homes with an HCC.


Leukemia
Lymphoma
Other
Total
HCC
52
10
17
79
LCC
84
21
31
136
Total
136
31
48
215
02

Simplify

As given, n=215

We know, expected count is r×cn

where r is row, c is column

The expected count of cases with lymphoma in homes with an HCC :

r=79c=31r×cn=79×31215

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