题目

A historian asserts that at the beginning of 1852, the population of a certain mining town was 16,000. The historian also asserts that for each of the years from 1849 through 1853, thetown’s population at the beginning of the year was twice that of the preceding year. According to the historian, what was the range of the town’s populations at the beginning of each year from 1848 through 1853?

选项

A.

14,000

B.

15,000

C.

28,000

D.

30,000

E.

31,000

解析

**按时间推进计算:** 1852年初的人口 = 16000 1853年初的人口 = 16000×2 = 32000 **回溯计算:** 1851年初的人口 = 16000÷2 = 8000 1850年初的人口 = 8000÷2 = 4000 1849年初的人口 = 4000÷2 = 2000 1848年初的人口 = 2000÷2 = 1000 1848-1853年的人口极差为: 32000 - 1000 = 31000 选项:E
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