Step-by-step explanation:
Total those who do chores = 8 + 20
Total of those who do chores = 28
Those who do chores but did not play sport = 20
percent of those who do chores but do not play sport = Those who do chores but did not play sport/Total of those who do chores × 100
percent of those who do chores but do not play sport = 20/28 × 100
percent of those who do chores but do not play sport = 71.4%