Answer:
.0625 or A
Step-by-step explanation:
You have to work out the mean. (The simple average of those numbers) Then for each number subtract the Mean and square the result. Then work out the average of those squared differences.
Answer:
C
Step-by-step explanation:
Gross taxable Income = $ 1,166
Rate of Income tax = 30%
Amount of income tax = 30 % of 1,166
= 
=$339.6
≅$340
Answer:
B
Step-by-step explanation:
Mathematically, we shall be using the z-score here
Z-score = (x-mean)/SD
From the question, mean = 80 and SD = 4
So we want to get the option in the question that has a z-score of 1 or below
Let’s look at 75
80-75 = 5 ( this is clearly above 1 standard deviation of 4)
For 77;
80 -77 = 3
This is less than the standard deviation of 4, meaning it is within 1 standard deviation of the mean
