题没说清楚是单选题还是多选题啊。如果全是单选题,有16种答案;至少800/16=50人做同样的。
如果是多选题:
共有:(4+6+4+1)*4=60种答案
13*60+20=800,所以至少14人答案一样。
答法可能是
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共有64*4=256种
根据抽屉原理解此题:800/256=3余32
所以至少有3人答案相同
50因为四道题目有四个选项4*4=16所以每个选项被选的概率是800/16=50既最少有50人选同样的答案
每题有4个选项,4道题就有4*4=16种答案。
800/16=50,
最少有50人选同样的答案。
每题的答法有5种可能,4个题有4*5=20种答案
所以至少有800/20=40
40个人的答究是相同的