Risks of playing soccer (1.1) A study in Sweden looked at former elite soccer players, people who had played soccer but not at the elite level, and people of the same age who did not play soccer. Here is a twoway table that classifies these individuals by whether or not they had arthritis of the hip or knee by their mid-fifties:37 Elite Non-Elite Did not play Arthritis 10 9 24 No arthritis 61 206 548

(a) What percent of the people in this study were elite soccer players? What percent had arthritis?

(b) What percent of the elite soccer players had arthritis?

What percent of those who had arthritis were elite soccer players?