Answer:
D
Step-by-step explanation:
Answer:
The z value is - 2.88
Step-by-step explanation:
The formula of the z-score of a population is z = (x¯ - μ)/(σ/
)
The given in the problem is:
- μ = 121
- σ = 21
- x¯ = 112.35
- n = 49
Let us substitute all of these values in the rule above

Simplify up and down


z = - 2.883333
Round it to 2 decimal places
∴ z = - 2.88
The z value is - 2.88
Answer:

Step-by-step explanation:
=> 
=> 
Since b = 11 , So
needs to be added to both sides
Adding
to both sides
=> 
Completing the square
=> 
=> 
Answer: B
Step-by-step explanation: i just did the question