Q30: The percentage of households with an annual income of more than $40,000 is higher in Merton county than in any other county. However, the percentage of households with an annual income of $60,000 or more is highest in Sommer county. If the statements above are true, which of the following can properly be concluded on the basis of them? A. No household in Merton county has an annual income of $60,000 or more. B. Some households in Merton county have an annual income between $40,000 and $60,000. C. The number of households with an annual income of more than $40,000 is greater in Merton than in Sommer county. D. Average annual household income is higher in Sommer than in Merton county. E. The percentage of households with an annual income of $80,000 is higher in Sommer than in Merton county. 标准答案为E,我选的B。 因为设M市40000-60000为A1,60000以上为B1,总人口为C1,S市相应A2, B2和C2,则有 (A1+B1)/C1>(A2+B2)/C2, B1/C1<B2/C2, 可推出A1/c1>A2/c2,同时A1/B1不能为0,否则第一个不等式就不成立了。而E却推不出来,请教各位。
[此贴子已经被作者于2004-12-13 4:39:50编辑过] |