Algebra 2
2 answers:
Answer:
Step-by-step explanation:
n=sample size =200
Mean = x bar = 55 hours
Std deviation (Population) = 7 hours
For 99% confidence level
Z critical value = 2.58
Margin of error = ±2.58(std error)
Std error =
Hence margin of error = ±0.495(258)=1.28
Confidence interval = (55-1.28, 55+1.28) = (53.72, 56.28)
~(53.73, 56.27)
Hence option A
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Hey there!
When we multiply fractions and whole numbers, we simply take that whole number and put it over them, and just multiply across. That gives us:
Notice how it's four, because when we have a fraction, we divide. 8 divided by 2 equals four. Next:
4/4 is equal to 1 because 4 divided by 4 is one. 4 goes into 4 once. Next, we have:
That's because 6/3 = 2.
Hope this helps!
When we multiply fractions and whole numbers, we simply take that whole number and put it over them, and just multiply across. That gives us:
Notice how it's four, because when we have a fraction, we divide. 8 divided by 2 equals four. Next:
4/4 is equal to 1 because 4 divided by 4 is one. 4 goes into 4 once. Next, we have:
That's because 6/3 = 2.
Hope this helps!