Answer:
And the best option would be:
c. 1450 +/- 12
Step-by-step explanation:
Information provided
represent the sample mean for the SAT scores
population mean (variable of interest)
represent the sample variance given
n=25 represent the sample size
Solution
The confidence interval for the true mean is given by :
(1)
The sample deviation would be
The degrees of freedom are given by:
The Confidence is 0.954 or 95.4%, the value of
and
, assuming that we can use the normal distribution in order to find the quantile the critical value would be
The confidence interval would be
And the best option would be:
c. 1450 +/- 12
The square root of 144 is 12
First do the ones in the parentheses. So, 2x3=6. 26-6=20. 20^2=400. Now you have 27-4x400. 4x400=1600. 27-1600=-1573.
Answer:
2
Step-by-step explanation:
let 'x' = number
x³ - x² = 2x
x³- x² - 2x = 0
x(x² - x - 2) = 0
x(x - 2)(x + 1) = 0
x = -1, 0, 2
the only positive solution is the number 2