{"msg":"第四节 算法（数值算法与非数值算法）的选择与应用","code":200,"data":{"currentIndex":null,"examId":null,"examTime":null,"questionList":[{"id":"796239536395931649","title":"某部门邀请3位专家对12个项目进行评选，每个专家选了5个项目。评选的结果中，有a个项目被3人都选中，有b个项目被2个选中，有c个项目被1人选中，有2个项目无人选中。据此，可以推断（52）。","analyze":"本题考查数学应用（方程求解分析）能力。<br>根据题意，a，b，c都是非负整数，a+b+c=12-2=10①，3a+2b+c=3X5=15②。由2①- ②可得c-a=5。<br>a=0时，c=5，b=5，c=a+b；<br>a=1时，c=6，b=3，c＞a+b；<br>a=2时，c=7，b=1，c＞a+b；<br>a＞2时，c＞7，a+c至少为11，与a+b+c=10矛盾。<br>根据上述情况，可以推断供选答案D是正确的。<br>(按汉语常规，a、b、c应均是正整数，a=0的情况不存在，此时应有结论c＞a+b)","multi":0,"questionType":1,"answer":"D","chooseItem":["796239537780051969"],"itemList":[{"id":"796239537683582977","questionId":"796239536395931649","content":" a&gt;2","answer":0,"chooseValue":"A"},{"id":"796239537721331713","questionId":"796239536395931649","content":" b&gt;5","answer":0,"chooseValue":"B"},{"id":"796239537750691841","questionId":"796239536395931649","content":" b为偶数","answer":0,"chooseValue":"C"},{"id":"796239537780051969","questionId":"796239536395931649","content":" c≥a+b","answer":1,"chooseValue":"D"}],"userAnswer":null,"userChooseItem":null,"answerCorrect":null,"userCollect":null}]}}