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%
9514 1404 393
Answer:
m∠Y = 40°
Step-by-step explanation:
The sum of complementary angles is 90°. If we let s and y represent m∠S and m∠Y, respectively, the angle measures in degrees satisfy ...
s + y = 90
(4y -110) +y = 90 . . . . . . . . substitute for s
5y = 200 . . . . . . . . . add 110
y = 40 . . . . . . . divide by 5
The measure of angle Y is 40°.
The probablity that the sample's mean length is greate than 6.3 inches is0.8446.
Given mean of 6.5 inches,standard deviation of 0.5 inches and sample size of 46.
We have to calculate the probability that the sample's mean length is greater than 6.3 inches is 0.8446.
Probability is the likeliness of happening an event. It lies between 0 and 1.
Probability is the number of items divided by the total number of items.
We have to use z statistic in this question because the sample size is greater than 30.
μ=6.5
σ=0.5
n=46
z=X-μ/σ
where μ is mean and
σ is standard deviation.
First we have to find the p value from 6.3 to 6.5 and then we have to add 0.5 to it to find the required probability.
z=6.3-6.5/0.5
=-0.2/0.5
=-0.4
p value from z table is 0.3446
Probability that the mean length is greater than 6.3inches is 0.3446+0.5=0.8446.
Hence the probability that the mean length is greater than 6.3 inches is 0.8446.
Learn more about probability at brainly.com/question/24756209
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Answer:
12 sorry if its wrong
Step-by-step explanation: