The sample proportion has an approximately normal distribution, with the mean being the population mean and the standard deviation (i.e. the standard error of the sampling proportion) equal to
SE = sqrt(p*q/n) where p is the population proportion q is 1-p, and n is the sample size.
<span>(Typically, for a confkdence interval, the sample proportion and its complement are substituted for p and q.) </span>
The margin of error will be Zc*SE, where Zc is the critical value of Z for the level of confidence required. The confidence interval, then, will be the sample proportion, plus or minus the margin of error.
For a 90% confidence interval, Zc is 1.645.
<span>So the margin of error is 1.645 * sqrt(.9*.1/400), roughly .025. So your confidence interval would be around [.875, .925]
The best and most correct answer among the choices provided by your question is the second choice or letter C which is 3%.
I hope my answer has come to your help. Thank you for posting your question here in Brainly.</span>
Answer:
A
Step-by-step explanation:
Answer:
15 minutes
Step-by-step explanation:
First, the motorcycle goes at a speed of 40 km/hr.
The question asks for how long it would take to travel 10 km.
Well, there are 60 minutes in an hour, since we will be translating into minutes.
Also, 10 km is 1/4 of 40 km, so it would make sense that the time length would be 1/4 of an hour as well.
1/4 of 60 minutes is 15 minutes. So it takes 15 minutes for the motorcycle to travel 10 km.
Now, if all this wordy stuff is too much to comprehend, you can also solve using proportional relationships.

Now cross multiply:

Divide both sides by 40:

Again, this shows that it wouls take 15 minutes for the motorcycle to travel 10 km.
Answer:no
Step-by-step explanation: No, because all the ratios of y to x are not equal.
Answer:
y=8
Step-by-step explanation: