Answer:

Using the frequency distribution, I found the mean height to be 70.2903 with a standard deviation of 3.5795
Step-by-step explanation:
Given
See attachment for class
Solving (a): Fill the midpoint of each class.
Midpoint (M) is calculated as:

Where
Lower class interval
Upper class interval
So, we have:
Class 63-65:

Class 66 - 68:

When the computation is completed, the frequency distribution will be:

Solving (b): Mean and standard deviation using 1-VarStats
Using 1-VarStats, the solution is:


<em>See attachment for result of 1-VarStats</em>
Answer:
It would be B (15x + 20x)
Answer:
28
Step-by-step explanation:
2x-3y+z=-3 , x-5y+7z=-11 , -10x+4y-6z=28