Combine like terms
-x = 4 + 6 - 3x
-x = 10 - 3x
Isolate the x, add 3x to both sides
-x (+3x) = 10 - 3x (+3x)
-x + 3x = 10
Simplify. Combine like terms
-x + 3x = 10
2x = 10
Isolate the x, divide 2 from both sides
2x/2 = 10/2
x = 10/2
x = 5
x = 5, or A is your answer
hope this helps
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
B and E are the correct answers, as 2/100 is the same thing as 0.02.
Answer:
Step-by-step explanation:
