Question

The numbers of trading cards owned by 9 middle- school students are given below. ( note that these are already ordered from least to greatest.

Answer 1

Given the numbers:

355, 382, 383, 427, 500, 572, 601, 638, 669

Total numbers = 9

a) We find the mean:

`\begin{gathered} mean=(355+382+383+427+500+572+601+638+669)/(9) \\ mean=(4527)/(9)=503 \end{gathered}`

Change 669 to 606:

`\begin{gathered} mean=(355+382+382+427+500+572+601+638+606)/(9) \\ mean=(4464)/(9)=496 \end{gathered}`

Then:

`\begin{gathered} mean=changed\text{ mean}-original\text{ mean} \\ mean=496-503=-7 \end{gathered}`

Answer: It decreases by 7

b) We find median

Median: 355, 382, 383, 427, 500, 572, 601, 638, 669

Median = 500

669 changed to 606

Median: 355, 382, 383, 427, 500, 572, 601, 606, 638

Median = 500

Answer: It stays the same