Problem of the Day
Joe took 20 equally weighted quizzes for his biology class and received an average score of 96% on those quizzes. If he received a grade of 96% on exactly 
of the quizzes, what is ?
(1) 
(2) 
Solution
[latexpage]
Statement 1: If he took 20 quizzes, and $n>18$ then either $n=19$ or $n=20$. However, it is impossible that $n=19$. If he were to score exactly 96% on 19 of the quizzes, then he would also have to score 96% on his 20th quiz to maintain the 96% average. Otherwise, his average would be slightly above or below 96%. SUFFICIENT.
Statement 2: $n\leq20$ doesn’t tell us anything we don’t already know. If he took 20 quizzes than obviously the number that he scored exactly 96% on is less than 20. INSUFFICIENT.
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