問題如下:
Since 1 january 2008,Mr.Lam invested 10% of his monthly salary in a
fund each month for the preparation of the future education expenditure
for his daughter.Suppose his monthly salary was$25000in2008and it
increases by2%each year,from which year will the amount of the
investment for the whole year start to be greater than $25000.
f6英文數(sequence)急
2012-08-29 2:00 am
回答 (2)
2012-08-29 3:07 am
✔ 最佳答案
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I hopethe solution can help you^^”
2012-08-28 20:01:23 補充：
2500(1.2^n -1)/0.2 >= 35000
1.2^n -1 >= 2.8
1.2^n >= 3.8
n ln 1.2 >= ln 3.8
n >= 7.32
Number of years = 8
2012-08-28 20:01:50 補充：
Therefore, the years = 2008+8 = 2016
參考: I hope the solution can help you^^”
2012-08-29 3:07 am
Let f(x)=25000x10%x(1+2%)^x
f(x)=2500x1.02^x
Since the investment for the whole year has to be greater than $25000,
f(x)>25000
2500x1.02^x>25000
1.02^x=10
x=log(1.02,10)
x=116months
x=9.69years=10years
The amount of investment for the whole year starts to be greater than $25000 in 2018.
f(x)=2500x1.02^x
Since the investment for the whole year has to be greater than $25000,
f(x)>25000
2500x1.02^x>25000
1.02^x=10
x=log(1.02,10)
x=116months
x=9.69years=10years
The amount of investment for the whole year starts to be greater than $25000 in 2018.
參考: me
收錄日期: 2021-04-16 14:54:10
原文連結 [永久失效]:
https://hk.answers.yahoo.com/question/index?qid=20120828000051KK00700