2005 AMC 12B Problems/Problem 4
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Problem
At the beginning of the school year, Lisa's goal was to earn an A on at least 
of her 
quizzes for the year. She earned an A on 
of the first 
quizzes. If she is to achieve her goal, on at most how many of the remaining quizzes can she earn a grade lower than an A?
Solution
Lisa's goal was to get an A on 
quizzes. She already has A's on quizzes, so she needs to get A's on 
more. There are 
quizzes left, so she can afford to get less than an A on 
of them.
