Answer:
475.
Step-by-step explanation:
We have been given that for a normal distribution with μ=500 and σ=100. We are asked to find the minimum score that is necessary to be in the top 60% of the distribution.
We will use z-score formula and normal distribution table to solve our given problem.

Top 60% means greater than 40%.
Let us find z-score corresponding to normal score to 40% or 0.40.
Using normal distribution table, we got a z-score of
.
Upon substituting our given values in z-score formula, we will get:





Therefore, the minimum score necessary to be in the top 60% of the distribution is 475.
165 new subs.
22 divided by 4 is 5.5. So approximately 5.5 new subs per day. Multiply that by 30 is 165
Answer:
-1 for question 1, -11 for question 2, 7 for question 3
Step-by-step explanation: