ABy Admin
Nov 18'23
Exercise
At an annual effective interest rate of 10.9%, each of the following are equal to X:
- The accumulated value at the end of n years of an n-year annuity-immediate paying 21.80 per year.
- The present value of a perpetuity-immediate paying 19,208 at the end of each n-year period.
Calculate X.
- 1555
- 1750
- 1960
- 2174
- There is not enough information given to calculate X
ABy Admin
Nov 18'23
Solution: C
From the first annuity,
[[math]]
X = 21.8 s_{\overline{n}|0.109} = 21.8\cdot{\frac{1.109^{n}-1}{0.109}}=200[1.109^{n}-1].
[[/math]]
From the second annuity,
[[math]]
X = 19,208( v^{n}+ v^{2n}+\cdots)=19,208{\frac{ v^{n}}{1- v^{n}}}=19,208{\frac{1}{1.109^{n}-1}}
[[/math]]
Hence,
[[math]]
\begin{array}{l}{{200[1.109^{n}-1]=19,208\frac{1}{1.109^{n}-1}}}\\ {{\mathrm{~[1.109^{n}-1]^{2}=19,208/200=96.04}}}\\ {{{ X=200(9.8)=1960.}}}\end{array}
[[/math]]