Answer:
One solution
Step-by-step explanation:
Let's rewrite y = 6 - 3x as y = -3x + 6
Looking at these two equations, we can see they share a y-intercept
Making our solution 6
We know there is only one solution because the equations are not the exact same, if they were we'd have infinitely many solutions
We also know there aren't no solutions because the lines are not parallel (same slopes with difference y-intercepts)
Best of luck
Answer:
they need to be in ratios format
Step-by-step explanation:
I think it’s 236.8 correct me if I’m wrong?
Answer:
21
Step-by-step explanation:
Using<em> Simple Random Sampling</em>, we can estimate the sample size by the formula
where
n = sample size
Z = the z-score corresponding to the confidence level 99.5%
S = the assumed standard deviation = 3 seconds
e = margin of error = 2 seconds
<em>It is worth noticing that the higher the confidence level, the larger the sample should be.
</em>
The z-score corresponding to a confidence level of 99.5% can be obtained either with a table or the computer and equals
Z = 3.023
Replacing the values in our formula
So the size of the sample should be at least 21.
Answer:
And rounded up we have that n=385
Step-by-step explanation:
Previous concepts
A confidence interval is "a range of values that’s likely to include a population value with a certain degree of confidence. It is often expressed a % whereby a population means lies between an upper and lower interval".
The margin of error is the range of values below and above the sample statistic in a confidence interval.
Normal distribution, is a "probability distribution that is symmetric about the mean, showing that data near the mean are more frequent in occurrence than data far from the mean".
Solution to the problem
In order to find the critical value we need to take in count that we are finding the interval for a proportion, so on this case we need to use the z distribution. Since our interval is at 99% of confidence, our significance level would be given by
and
. And the critical value would be given by:
The margin of error for the proportion interval is given by this formula:
(a)
And on this case we have that
and we are interested in order to find the value of n, if we solve n from equation (a) we got:
(b)
We can use as an estimator for p
. And replacing into equation (b) the values from part a we got:
And rounded up we have that n=385