The z- score is the number of standard deviations from the mean value of the reference population.
For example: the z-score of 2 is 2 standard deviations above the mean.
The z -score of a value that is 2.08 standard deviations greater than the mean is 2.08.
Answer:
0.3721 or 37.21%
Step-by-step explanation:
P(I) = 0.60; P(II) = 0.40;
P(not defective I) = 0.90; P(not defective II) = 0.80
The probability that the phone came from factory II, given that is not defective, is determined by the probability of a phone from factory II not being defective divided by the probability of a phone not being defective.

The probability is 0.3721 or 37.21%.
One number is 26 the other is 23
x+y=49
Y=x+3,X (now substitute it in the equation)
x+3+x=49
2x+3=49
2x=46. X=23
Y=x+3. Y=23+3 =26 for checking 23+26=49
$630
The total perimeter is 42 and 42x15=630