<h3>Answer: B) 31.348</h3>
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Work Shown:
We will never use the alpha = 0.05 value when computing the test statistic. So we can ignore alpha for this particular problem.
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n = 40 is the sample size.
s = 2.6 is the sample standard deviation
= sigma = 2.9 is the population standard deviation (ie the claimed standard deviation for all the pay phones)
Test Statistic for chi-square
2x + (x+9) = 90
3x + 9= 90
3x= 81
x= 27
Now plug in 27 to (x+9)
27+9= 36
Final Answer = 36
Start with an equation.
Nine less... so -9
3 times a number = 3x
Greater than 40 is >40
So put together is 3x-9>40
When solving I imaging the greater than sign as an equal sign. Less confusing.
3x-9=40
3x=49
x>49/3
Answer:
x^2-4/7x-12/49=0
x= 6/7 and -2/7
Step-by-step explanation:
Multiply 10 times 5 then divide it by 4
