数据：1，5，6，5，6，5，6，6的众数是______，中位数是______，方差是______．
将数据从小到大依次排列为1，5，5，5，6，6，6，6．众数是6，中位数是（5+6）÷2=5.5，平均数是（1+5×3+6×4）÷8=40÷8=5．方差为
[（1-5）2+3（5-5）2+4（5-6）2]=1 8
．5 2
故填6，5.5，
．5 2
| 完形填空。 Dear Ann, 1 are you? Do you 2 your school? I like my school a lot. My teachers are very 3 . Some of my classes are 4 , but some of them are boring. I like English and art, 5 I don't like math. My brother likes 6 school, too. He likes math, but he 7 like science. His favorite 8 is PE. He likes 9 a lot. Does your sister like her 10 ? What subjects do you like? Emma | ||||
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