Answer: i'm pretty sure the answer is C
Step-by-step explanation:
Answer:
Answer for the question:
The Rockwell hardness of a metal is determined by impressing a hardened point into the surface of the metal and then measuring the depth of penetration of the point. Suppose the Rockwell hardness of a particular alloy is normally distributed with mean 69 and standard deviation 2.7.
a. If a specimen is acceptable only if its hardness is between 67 and 75, what is the probability that a randomly chosen specimen has an acceptable hardness?
b. If the acceptable range of hardness is (69-C, 69+C), for what value of C would 95% of all specimens have acceptable hardness?
c. If the acceptable range is as in part (a) and the hardness of each of ten randomly selected specimens is independently determined, what is the expected number of acceptable specimens among the ten?
d. What is the probability that at most eight of ten independently selected specimens have a hardness of less than 72.84(HINT Y=number among the ten specimens with hardness less than72.84 is a binomial variable; what is p?)
is given in the attachment.
Step-by-step explanation:
Step-by-step explanation:
I think the first number is 2
Then 2 x 2 = 4 so there is a difference of 4 number
Then in between 6 and 14 there is a difference of 8 so 4 x 2 = 8
Then 16 so 8 x 2 = 16
So after 126 the number is 254
Answer:
-6x-10y
Step-by-step explanation:
Multiply -2 by everything in parenthesis
A² + b² = c²
5² + 8² = x²
x² = 25 + 64
x² = 89
x = √89
x = 9.43
