For large sample confidence intervals about the mean you have:
xBar ± z * sx / sqrt(n)
where xBar is the sample mean z is the zscore for having α% of the data in the tails, i.e., P( |Z| > z) = α sx is the sample standard deviation n is the sample size
We need only to concern ourselves with the error term of the CI, In order to find the sample size needed for a confidence interval of a given size.
z * sx / sqrt(n) = width.
so the z-score for the confidence interval of .98 is the value of z such that 0.01 is in each tail of the distribution. z = 2.326348
The equation we need to solve is:
z * sx / sqrt(n) = width
n = (z * sx / width) ^ 2.
n = ( 2.326348 * 6 / 3 ) ^ 2
n = 21.64758
Since n must be integer valued we need to take the ceiling of this solution.
n = 22
Answer:
85-7-19 or 85-26
Step-by-step explanation:
They stayed at the beach for 7 days. 4 x 3 = 12. 12 - 5 = 7
Step 1: Factor out variable m.<span><span>m<span>(<span><span>−<span>50n</span></span>+35</span>)</span></span>=<span>3p</span></span>Step 2: Divide both sides by -50n+35.<span><span><span>m<span>(<span><span>−<span>50n</span></span>+35</span>)</span></span><span><span>−<span>50n</span></span>+35</span></span>=<span><span>3p</span><span><span>−<span>50n</span></span>+35</span></span></span><span>m=<span><span>3p</span><span><span>−<span>50n</span></span>+35</span></span></span>Answer:<span>m=<span><span><span>3p</span><span><span>−<span>50n</span></span>+35</span></span></span></span>
