Any decimal that has a finite number of nonzer
问题详情
Any decimal that has a finite number of nonzero digits is a terminating decimal. For example, 16, 12.43, and 0.26 are all terminating decimals. If a and b are positive integers and the ratio a/b is expressed as a decimal, is a/b a terminating decimal？
(1) b=5
(2) 70＜a＜80请帮忙给出正确答案和分析，谢谢！
参考答案
正确答案：A
A 解析：alone is sufficient because any positive integer divided by 5 will have a remainder of either 0, 1, 2, 3, or 4, which translate into terminating decimals of either 0.0, 0.2, 0.4, 0.6, or 0.8; therefore, if b=5, then a/b has to be a terminating decimal. (2) alone is insufficient because it does not give the value for b;, if, for example, b=5, then any of the numbers in that range would result in terminating decimals, but if b=3, then 71/3=23.666666666....
