The average (arithmetic mean) of 16 students first quiz scores in a difficult English class is 62.5. When one student dropped the class, the average of the remaining scores increased to 63.0. What is the quiz score of the student who dropped the class?
Pick:
A) 10
B) 25
C) 40
D) 55
E) 70

Rationale: total score of 16 students is 16 * 62.50 = 1000 total score of 15 students is 15 * 63 = 945 so , the score of the person who left is 55 ( 1000 - 945 ) answer will be ( d )
Answer: D