I'm going to assume that you are trying to find the two numbers. Based on the information in the problem, we can create the following equations (where and
are the two numbers):
We have a systems of equations. In this case, it would be easier to use elimination by adding vertically. This produces the result:
To find , substitute the value for
into one of the earlier equations:
The two numbers are 12 and 18.
Answer:
option A
Step-by-step explanation:
given,
10% A grades 80% B grades 10% C grades
This year, managers with scores less than 35 received C's and those with scores above 425 received A's.
The mean has to be middle of two corresponding cutoff value
μ = 230
Cutoff Off C grade corresponds with the area of 0.10 is table A.
corresponding z- score according to Table A
Z = -1.28
now, standard deviation
σ = 152.3
Correct answer is option A