Revision as of 12:02, 18 November 2023 by Admin (Created page with "'''Solution: B''' <math display = "block"> \begin{aligned} & 475 a_{\overline{10} \mid i}=400\left(a_{5 \mid i}+v^{10} a_{\infty}\right) \\ & 475 \frac{1-v^{10}}{i}=400 \frac{1-v^5+v^{10}}{i} \\ & 475\left(1-v^{10}\right)=400\left(1-v^5+v^{10}\right) \\ & 875 v^{10}-400 v^5-75=0 \\ & v^5=\frac{400 \pm \sqrt{400^2+4(875)(75)}}{2(875)}=0.6 \\ & i=(1 / 0.6)^{1 / 5}-1=0.1076=10.76 \%\end{aligned} </math> {{soacopyright | 2023 }}")
Exercise
ABy Admin
Nov 18'23
Answer
Solution: B
[[math]]
\begin{aligned} & 475 a_{\overline{10} \mid i}=400\left(a_{5 \mid i}+v^{10} a_{\infty}\right) \\ & 475 \frac{1-v^{10}}{i}=400 \frac{1-v^5+v^{10}}{i} \\ & 475\left(1-v^{10}\right)=400\left(1-v^5+v^{10}\right) \\ & 875 v^{10}-400 v^5-75=0 \\ & v^5=\frac{400 \pm \sqrt{400^2+4(875)(75)}}{2(875)}=0.6 \\ & i=(1 / 0.6)^{1 / 5}-1=0.1076=10.76 \%\end{aligned}
[[/math]]
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