prep DS1 144题，求NN帮我解答

hanlei84921

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

season5924

我问你，如果r解出来大于百分之七，你能判断么？