Answer:
65
Step-by-step explanation:
Answer:
The p value for this case can be calculated with this probability:
Since the p value is higher than significance level we don't have enough evidence to conclude that the true proportion is significantly less than 0.1
Step-by-step explanation:
Information given
n=310 represent th sample selected
X=28 represent the subjects wrong
estimated proportion of subjects wrong
is the value to verify
represent the significance level
t would represent the statistic
represent the p value
System of hypothesis
We want to test the claim that less than 10 percent of the test results are wrong ,and the hypothesis are:
Null hypothesis:
Alternative hypothesis:
The statistic is given by:
(1)
Replacing the info we got:
The p value for this case can be calculated with this probability:
Since the p value is higher than significance level we don't have enough evidence to conclude that the true proportion is significantly less than 0.1
2n^2-8n=9
divide by 2
2(n^2-4n) =9
add (4/2)^2 =4 to each side completing the square
(n^2-4n+4 ) =9/2+4
(n-2)^2 = 9/2+8/2
(n-2)^2 =17/2
take the square root of each side
n-2 = +-sqrt(17/2)
add 2 to each side
n = 2+- sqrt (17/2)
Answer:2+ sqrt (17/2),2- sqrt (17/2)
Make all the fractions improper, add it, and simplify 17/4
4 1/4
make all fractions improper, subtract, simplify
28/8
3 1/2