Answer:
Step-by-step explanation:
Probability = 4/46 = 2/23
(2/23) *100 = 200/23 = 8.69% = 8.7%
You need to know these two formulas:

For example,

Answer:
A. 31/100
Step-by-step explanation:
Change 3/10 to hundreds:
3/10 × 10/10 = 30/100
The denominator (the bottom number) must be 100.
61 - 30 is 31.
The missing number is 31/100. See image.
Given Information:
Mean weekly salary = μ = $490
Standard deviation of weekly salary = σ = $45
Required Information:
P(X > $525) = ?
Answer:
P(X > $525) = 21.77%
Step-by-step explanation:
We want to find out the probability that a randomly selected teacher earns more than $525 a week.

The z-score corresponding to 0.78 from the z-table is 0.7823

Therefore, there is 21.77% probability that a randomly selected teacher earns more than $525 a week.
How to use z-table?
Step 1:
In the z-table, find the two-digit number on the left side corresponding to your z-score. (e.g 0.7, 2.2, 1.5 etc.)
Step 2:
Then look up at the top of z-table to find the remaining decimal point in the range of 0.00 to 0.09. (e.g. if you are looking for 0.78 then go for 0.08 column)
Step 3:
Finally, find the corresponding probability from the z-table at the intersection of step 1 and step 2.
2/3, 4/5, 1/8 is the correct order from greatest to least.