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%
The value would be more than c
Answer:
B=3.6h
Step-by-step explanation:
I had the same question on my hw and I guessed that and got it right so
Binomial distribution formula: P(x) = (n k) p^k * (1 - p)^n - k
a) Probability that four parts are defective = 0.01374
P(4 defective) = (25 4) (0.04)^4 * (0.96)^21
P(4 defective) = 0.01374
b) Probability that at least one part is defective = 0.6396
Find the probability that 0 parts are defective and subtract that probability from 1.
P(0 defective) = (25 0) (0.04)^0 * (0.96)^25
P(0 defective) = 0.3604
1 - 0.3604 = 0.6396
c) Probability that 25 parts are defective = approximately 0
P(25 defective) = (25 25) (0.04)^25 * (0.96)^0
P(25 defective) = approximately 0
d) Probability that at most 1 part is defective = 0.7358
Find the probability that 0 and 1 parts are defective and add them together.
P(0 defective) = 0.3604 (from above)
P(1 defective) = (25 1) (0.04)^1 * (0.96)^24
P(1 defective) = 0.3754
P(at most 1 defective) = 0.3604 + 0.3754 = 0.7358
e) Mean = 1 | Standard Deviation = 0.9798
mean = n * p
mean = 25 * 0.04 = 1
stdev = 
stdev =
= 0.9798
Hope this helps!! :)