Answer:
[tex]\begin{array}{ccc}{Midpoint} & {Class} & {Frequency} & {64} & {63-65} & {1} & {67} & {66-68} & {11} & {70} & {69-71} & {8} &{73} & {72-74} & {7} & {76} & {75-77} & {3} & {79} & {78-80} & {1}\ \end{array}[/tex]
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:
[tex]M = \frac{1}{2}(Lower + Upper)[/tex]
Where
[tex]Lower \to[/tex] Lower class interval
[tex]Upper \to[/tex] Upper class interval
So, we have:
Class 63-65:
[tex]M = \frac{1}{2}(63 + 65) = 64[/tex]
Class 66 - 68:
[tex]M = \frac{1}{2}(66 + 68) = 67[/tex]
When the computation is completed, the frequency distribution will be:
[tex]\begin{array}{ccc}{Midpoint} & {Class} & {Frequency} & {64} & {63-65} & {1} & {67} & {66-68} & {11} & {70} & {69-71} & {8} &{73} & {72-74} & {7} & {76} & {75-77} & {3} & {79} & {78-80} & {1}\ \end{array}[/tex]
Solving (b): Mean and standard deviation using 1-VarStats
Using 1-VarStats, the solution is:
[tex]\bar x = 70.2903[/tex]
[tex]\sigma = 3.5795[/tex]
See attachment for result of 1-VarStats
