标题: 一道数学题，有点看不懂 [打印本页] 作者: woaihenglia 时间: 2011-1-31 07:23 标题: 一道数学题，有点看不懂 1:In the equation above, k,r,s,t, and v represent positive numbers. Multiplying which one of these numbers by 2 will reduce the value of n to1/2 of its present value?
后半句啥意思？翻译一下
选项分别是k,r,s,t,v
2: A certain money market account that had a balance of $48,000 during all of last month earned $360 in interest for the month. At what simple annual interest rate did the account earn interest last month?
A 7% B 7.5% C 8% D8.5% E 9%
这道题咋做。作者: sdcar2010 时间: 2011-1-31 08:19
n = f(k,r,s,t,v)
Replace x, wherein x is chosen from the group of k,r,s,t, and v, with 2*x, then the value of n, when x becomes 2x, would be cut in half.