Answer:
<em>Grades to be scored in 3rd exam = 88</em>
Step-by-step explanation:
Given that average of 3 numbers is 85.
First two numbers are 81 and 86.
To find:
3rd number so that average is 85
Solution:
Let the third number = 
Formula for average is:

Here, sum of numbers = 
Total count of numbers = 3

<em>Grades to be scored in 3rd exam = 88</em>
-10/8 and + 15/8. Those should work.
Answer:
Here is the solution . see the attached file
Answer:
A) About $195.00
Step-by-step explanation:
In a normal distribution, the interval (mean - 3*standard deviation, mean + 3*standard deviation) account for about 99.7% of the values. In this case mean + 3*standard deviation = $87.00 + 3*$36.00 = $195.00. So, it 's expected that this amount of money would be the largest individual customer bill.