Condition improved 1 No change N Condition worse W c P MU W Total Check Clear b E A participant saw their condition get worse P E Check Clear Used medication M Used placebo L 100 500 100 300 3800 4000 Let M be the event that a participant used the medication L the event that a participant used the placebo I the event a the participant s condi improved and so on as shown by the letters in the headings Find the relative frequency in each case a P I Check Clear d F A participant used the placebo or saw no change in their condition P F Check Clear 200 e GA participant whose condition improved used the placebo 1000 Total 600 400 4000 5000