To determine if there is an association between the number of miles runners run per week and the number of pairs of running shoes they purchase per year, we can create a relative frequency table and analyze the data.
Relative Frequency Table:
| | Purchases > 2 Pairs | Purchases ≤ 2 Pairs | Total | |---------------------|----------------------|----------------------|-------| | Runs > 5 miles/week | 42 | 28 | 70 | | Runs ≤ 5 miles/week | 15 | 32 | 47 | | Total | 57 | 60 | 117 |
Now, we can compute the relative frequencies for each category:
-
Relative frequency of runners purchasing more than 2 pairs of shoes and running more than 5 miles/week:
\( \frac{42}{117} \approx 0.359 \) (or 35.9%) -
Relative frequency of runners purchasing ≤ 2 pairs of shoes and running more than 5 miles/week:
\( \frac{28}{117} \approx 0.239 \) (or 23.9%) -
Relative frequency of runners purchasing more than 2 pairs of shoes and running ≤ 5 miles/week:
\( \frac{15}{117} \approx 0.128 \) (or 12.8%) -
Relative frequency of runners purchasing ≤ 2 pairs of shoes and running ≤ 5 miles/week:
\( \frac{32}{117} \approx 0.273 \) (or 27.3%)
Conclusion: Based on the relative frequencies, a larger proportion of runners who run more than 5 miles per week purchase more than 2 pairs of shoes (35.9%) compared to those who run 5 miles or less and purchase more than 2 pairs (12.8%). This suggests a positive association between running more miles per week and the likelihood of purchasing more running shoes. Thus, it can be reasoned that the greater the mileage run per week, the more pairs of shoes are purchased by that individual.