Z = √(10^2 + 8^2 - 2 *10 * 8 * cos(z)
z = arccos(1/8
A = 82.8
Answer is D.
In any right triangle with a 45 degree angle. The hypotenuse is the length of the side times √2
The answer is 8√2
The correct interpretation of the p-value is given by:
B If the average battery life really is 5 hours, then a sample of 10 observations having a sample mean of 4.25 hours or lower would only occur about 3.8% of the line.
<h3>How to find the p-value of a test?</h3>
It depends on the test statistic z, as follows:
- For a left-tailed test, it is the area under the normal curve to the left of z, which is the p-value of z.
- For a right-tailed test, it is the area under the normal curve to the right of z, which is 1 subtracted by the p-value of z.
- For a two-tailed test, it is the area under the normal curve to the left of -z combined with the area to the right of z, hence it is 2 multiplied by 1 subtracted by the p-value of z, which means that the p-value for a two-tailed test is twice the p-value of a one-tailed test.
In this problem, a left-tailed test is used, as we are testing if the mean is less than 5 hours.
The sample mean from the 10 times was of 4.25, and the p-value is of 0.038, which means that the area to the left of Z under the normal curve is of 0.038, that is, a sample mean of 4.25 hours or lower would only occur about 3.8% of the line, hence option B is correct.
You can learn more about p-values at brainly.com/question/13873630
Answer:
52%
Step-by-step explanation:
First, find the difference between this year's sales and the previous'. 1500-990=510.
Now we can divide 990 by 510 to find the percent increase. 510/990=0.515151515152, or 52%.
