某校举办2010年上海世博会知识竞赛，从参赛的高一、高二学生中各抽100人的成绩作为样本，其结果如下表：
（Ⅱ）你有多大的把握认为“高一、高二两个年级这次世博会知识竞赛的成绩有差异”． |
（Ⅰ）由图表可得，m=60，n=20；
（Ⅱ）设a=80，b=60，c=20，d=40．
则a+b=140，c+d=60，a+c=100，b+d=100．
ad=3200，bc=1200．
所以k=n(ad-bc)2 (a+b)(c+d)(a+c)(b+d)
=
≈9.5．200×(3200-1200)2 140×60×100×100
K2的观测值k=9.5＞7.879，所以有99.5%的把握认为“高一、高二两个年级这次世博会知识竞赛的成绩有差异”．
| 阅读理解。 | |
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| 1. If a group of twelve children went to see The Bilbies, they would ________. | |
| A. have special seats B. spend less money C. be asked to buy family tickets D. have to buy the tickets on Tuesday | |
| 2. The poster tells us at the Pilgrim Theatre there were at least ________. | |
| A. 2 performances B. 19 performances C. 21 performances D. 34 performances | |
| 3. According to the poster, which of the following is true? | |
| A. At Parramatta Town Hall there were 2 performances. B. Parramatta Town Hall is one minute walk from Town Hall Station. C. The audience most likely to enjoy the show, The Bilbies, would be children. D. A family of five would have to pay 38 dollars to see The Bilbies. |