在七年级第九章不等式与不等式组学习中,发现有不少的学生在一元一次不等式与实际问题中容易发生一个错误,而有个别教师往往会忽视这个错误.例:①在“科学与艺术”知识竞赛的预赛中共有20道题,对于每一道题,答对得10分,答错或不答扣5分,总得分不少于85分者通过预选赛,某中学学生通过了预选赛,至少答对了多少道题? In Chapter 7, Chapter 9, Inequality and Inequality Learning, I found that many students are prone to a mistake in the unary inequality and the practical problems, but some teachers tend to ignore this mistake. Art "quiz 20 questions, 10 points for each question, 10 points for the wrong answer or not, with a total score of 85 points or more Qualifying, a junior high school student passed the preselection Match, at least, how many questions right?