Answer:
i)The correct option is D.) 99.74%
ii) The correct option is B.) 68.26%
Step-by-step explanation:
i) P(10≤X≤70) = P( (10−40)/10 ≤Z≤ (70−40
)/10 ) = Pr(−3≤Z≤3)
= 0.9987 - 0.0013 = 0.99734
Therefore the percentage of Jen's monthly phone bills are between $40 and $100 is D.) 99.74%
ii)P(2.1≤X≤3.1) = P( (2.1 − 2.6) /0.5 ≤ Z ≤ (3.1−2.6
)/0.5) = Pr(−1 ≤Z ≤1)
)
= 0.8413 − 0.1587 = 0.6826
Therefore the percentage of students at college have a GPA between 2.1 a,d 3.1 is B.) 68.26%
Answer: 2 or more.
X and Y could be anything, so there are at least two answers
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
Answer:
<em>x</em> = 9.
Step-by-step explanation:
If you meant (x + 13) = 24, then we first must subtract 24 by 13.
24 - 13 = 9
Now, check your work by replacing the "x" with 9.
(9+ 13) = 24
24 = 24 <----- This is a true statement.
Therefore, <em>x</em> = 9.
Hope this helps! :D