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Mice21 [21]
3 years ago
5

There is concern that increased industrialization may be increasing the mineral content of river water. Ten years ago, the silic

on content of the water in a certain river was 5 mg/L. Eighty-five water samples taken recently from the river have mean silicon content 5.4 mg/L and standard deviation 1.2 mg/L. a. Find the P-value. b. Do you believe it is plausible that the silicon content of the water is no greater than it was 10 years ago
Mathematics
1 answer:
Tema [17]3 years ago
6 0

Answer:

a) P value = 0.0013

b) No, it is not plausible that the silicon content of the water is no greater than it was 10 years ago

Step-by-step explanation:

The null hypothesis here is “Mean is equal to 5” while alternate hypothesis is that “Mean is greater than 5”

Given  

Mean = 5, x’ = 5.4 and sigma = 1.2 and n = 85

Z = x-u’/sigma/sqrt n

Substituting the given values, we get –  

Z = 3.02

A) P value = 0.0013 which is less than 0.05 and thus we will reject the null hypothesis

B) There is enough evidence to reject the null hypothesis  

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Suppose 12% of students are veterans. From a sample of 263 students, how unusual would it be to have less than 22 veterans?
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Step-by-step explanation:

Given that :

p = 12% = 0.12 ;

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