ChaseDream

标题: 求解答一道Prep数学题 [打印本页]

作者: pzychloe    时间: 2015-9-22 11:04
标题: 求解答一道Prep数学题
遇到一题prep 数学题。没有理解高亮部分。是说interest rate 一样,monthly installments 都一样, 但是为什么问题又问John's monthly installment was what percent of Sue's? 谢谢
If a loan of P dollars, at an interest rate of r percent per year compounded monthly, is payable in n monthly installments of m dollars each, then m is determined by the formula:

m = (rP/1200)/( 1 - (1 + r/1200)^-n)

John and Sue took out loans whose monthly installments were determined by using the formula above. Both loans had the same interest rate and the same number of monthly installments. John's monthly installment was what percent of Sue's monthly installment?

(1) The amount of Sue's loan was 4 times the amount of John's loan.

(2) Sue's monthly installment was 4 times John's monthly installment.
作者: jaydenzhao    时间: 2015-9-22 11:25
这道题选D吧? the same number of monthly installments 指的应该是n一致,并不是指代 monthly installments 相等。注意是the number一致,就是还款年限。
作者: pzychloe    时间: 2015-9-23 10:11
jaydenzhao 发表于 2015-9-22 11:25
这道题选D吧? the same number of monthly installments 指的应该是n一致,并不是指代 monthly installmen ...

谢谢。理解了:)
作者: lighthousecn    时间: 2015-9-23 12:46
r,n一样,正比于P
只看P就OK了
作者: pzychloe    时间: 2015-9-24 09:20
lighthousecn 发表于 2015-9-23 12:46
r,n一样,正比于P
只看P就OK了

同意!               




欢迎光临 ChaseDream (https://forum.chasedream.com/) Powered by Discuz! X3.3