unlike the coefficient of determination, the sample correlation coefficient in a simple linear regression . multiple choice can
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Answer:
a) The margin of error for a 90% confidence interval when n = 14 is 18.93.
b) The margin of error for a 90% confidence interval when n=28 is 12.88.
c) The margin of error for a 90% confidence interval when n = 45 is 10.02.
Step-by-step explanation:
The t-distribution is used to solve this question:
a) n = 14
The first step to solve this problem is finding how many degrees of freedom, we have. This is the sample size subtracted by 1. So
df = 14 - 1 = 13
90% confidence interval
Now, we have to find a value of T, which is found looking at the t table, with 13 degrees of freedom(y-axis) and a confidence level of . So we have T = 1.7709
The margin of error is:
In which s is the standard deviation of the sample and n is the size of the sample.
The margin of error for a 90% confidence interval when n = 14 is 18.93.
b) n = 28
27 df, T = 1.7033
The margin of error for a 90% confidence interval when n=28 is 12.88.
c) The margin of error for a 90% confidence interval when n = 45 is
44 df, T = 1.6802
The margin of error for a 90% confidence interval when n = 45 is 10.02.
Answer:
2.10 s, 10.40 s.
Step-by-step explanation:
We know that the height of the rocket is given by the function:
We are asked to find the time for which the height of the rocket will be 350 ft. So, for that moment, we know the height but we don't know the time; however, we know that the equation can help us to find the time, doing h=350:
The last is a quadratic equation, which can be put in the form and solved applying the formula:
So, let's put the equation on the form adding
and subtracting
to each side of the equation; the result is:
So, we note that a=16, b=-200, and c=350.
Then,
According to the equation, that are the times for which the height will be 350 ft; that is because the rocket is going to ascend and then to fail again to the ground.