Final answer:
Mr. Riley made 60% of his 3-pt shots by making 18 out of 30 attempts.
Step-by-step explanation:
Mr. Riley made 18 shots out of 30 attempts from behind the 3-pt line. To find out what percent of the shots he made, we use the formula for percentage: (Number of Successful Outcomes/Total Number of Attempts) × 100. Following this formula:
(18 shots made / 30 shots attempted) × 100 = 0.6 × 100 = 60%.
Therefore, Mr. Riley made 60 percent of his shots from behind the 3-pt line.