Question

A Distance Run (km) B Distance Run (km) 0889 1 1/2 2 4 5 4 55 5 1 8 2 1 1/367 0 1 1 1 24 77 1 2 3 3 6 8 9 3 5 5 6 7 8 9 3 10 034 4 5 310 What is the DIFFERENCE in the MEANS of the 2 sets of data? Type your answer without a label.

Answer 1

To find the mean, we have to add all the numbers to then divide that sum by the total number of elements.

Chart A.

Let's sum each row.

8 + 8 + 9 = 25

1 + 2 + 2 + 4 + 5 + 5 + 8 = 27

1 + 1 + 3 + 6 + 7 = 18

0 + 3 + 4 + 4 + 5 = 16

$\bar{x}=\frac{25+27+18+16}{4}=\frac{86}{4}=21.5$

The mean of chart A is 21.5.

Chart B.

1 + 1 + 2 + 4 + 7 + 7 = 22

2 + 3 + 3 + 6 + 8 + 9 = 31

3 + 5 + 5 + 6 + 7 + 8 + 9 = 43

$\bar{x}=\frac{22+31+43+0}{4}=\frac{96}{4}=24$

Then, we subtract

$24-21.5=2.5$

Hence, the difference between the means is 2.5.