At the opening of a trading day at a certain stock exchange, the price per share of stock K was $15. If the price per share of stock K was $16 at the closing of the day, what was the percent increase in the price per share of stock K for that day? Choose the correct option.
A) 1.4 % B) 5.9 % C) 11.1 % D) 6.67 % E) 23.6 %

Rationale: "opening = 15 closing = 16 rise in price = 1 so , percent increase = 1 / 15 * 100 = 6.67 answer : d"
Answer: D