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prep DS1 144
If $1,000 is deposited in a certain bank account and remains in the account along with any accumulated interest, the dollar amount of interest, I , earned by the deposit in the first n years is given by the formula I
=1000〔(1 + r/100)n - 1〕, where r percent is the annual interest rate paid by the bank. Is the annual interest rate paid by the bank greater than 8 percent?
(1) The deposit earns a total of $210 in interest in the first two years.
(2) ( 1 + r/100)2 > 1.15
我觉得2这个式子从理论上能够算出r的值，既然能够计算出r，那么就可以跟8比较大小啊，为什么答案是A呢，哪位大NN能帮忙解答一下啊
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