Answer:
0.13% of customers spend more than 46 minutes
Step-by-step explanation:
Problems of normally distributed samples are solved using the z-score formula.
In a set with mean 
and standard deviation 
, the zscore of a measure X is given by:
The Z-score measures how many standard deviations the measure is from the mean. After finding the Z-score, we look at the z-score table and find the p-value associated with this z-score. This p-value is the probability that the value of the measure is smaller than X, that is, the percentile of X. Subtracting 1 by the pvalue, we get the probability that the value of the measure is greater than X.
In this problem, we have that:
What percentage of customers spend more than 46 minutes?
This is 1 subtracted by the pvalue of Z when X = 46. So
has a pvalue of 0.9987
1 - 0.9987 = 0.0013
0.13% of customers spend more than 46 minutes
Answer:
(c) H0 should be rejected
Step-by-step explanation:
Null hypothesis (H0): population mean is equal to 5
Alternate hypothesis (Ha): population mean is greater than 5
Z = (sample mean - population mean) ÷ (sd/√n)
sample mean = 5.3, population mean = 5, sd = 1, n = 500
Z = (5.3 - 5) ÷ (1/√500) = 0.3 ÷ 0.045 = 6.67
Using the normal distribution table, for a one tailed test at 0.01 significance level, the critical value is 2.326
Conclusion:
Since 6.67 is greater than 2.326, reject the null hypothesis (H0)
Answer:
(-6,-4)
Step-by-step explanation:
Hope this helps! (:
<h3>
Answer: -19, -15, -9, -1, 9 (choice A)</h3>
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Explanation:
If we plug in x = -2, then we get,
y = x^2 + 7x - 9
y = (-2)^2 + 7(-2) - 9
y = 4 - 14 - 9
y = -10 - 9
y = -19
So x = -2 leads to y = -19. The answer is between A and D.
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If you repeat those steps for x = -1, then you should get y = -15
Then x = 0 leads to y = -9
x = 1 leads to y = -1
Finally, x = 2 leads to y = 9
The outputs we get are: -19, -15, -9, -1, 9 which is choice A
Choice D is fairly close, but we won't have a second copy of -15, and we don't have an output of -19.
