Given:
75,78,81,90,95, 97,100
Mean before the change.
Mean =
[tex]\begin{gathered} \text{Mean}=\frac{\Sigma X}{n} \\ \\ =\frac{75+78+81+90+95+97+100}{7} \\ \\ =\frac{616}{7} \\ \\ =88 \end{gathered}[/tex]Hence, mean before the change = 88
Mean after the change
82,78,81,90,95, 97,100
[tex]\begin{gathered} \text{Mean}=\frac{82+78+81+90+95+97+100}{7} \\ \\ =\frac{623}{7} \\ \\ =89 \end{gathered}[/tex]Hence, mean after the change = 89
Median before the change.
To find the median, re-arrange the numbers in ascending order and pick the middle number.
That is;
75, 78 ,81, 90, 95, 97,100
The middle number is 90
Hence, median before the change = 90
Median after the change
82,78,81,90,95, 97,100
Re-arrange from lowest to highest.
78, 81,82, 90, 95, 97, 100
The middle number is 90.
Hence, the median after the change is 90.
