<<echo=FALSE, results=hide>>=
discountrate <- round(runif(1, min = 6.0, max = 15.0), 2)
r <- discountrate / 100.0

cf0 <- sample(10:20, 1) * -100
ocf <- sample(seq(200, 500, 25), 5)
discounts <- sapply(1:5, function(i) (1 + r) ** i)
npv <- round(sum(ocf / discounts) + cf0, 2)

notvm <- round(sum(ocf) + cf0, 2)
wrongtvm <- round(sum(ocf / (1.0 + r)) + cf0, 2)
revtvm <- round(sum(ocf * (1.0 + r)) + cf0, 2)
offnpv <- round(npv + sample(c(-200.0, 200.0), 1), 2)
@

\begin{question}
Assuming the discount rate is \Sexpr{discountrate}\%, find the 
net present value of a project with the following cash flows, starting
at time 0: \$\Sexpr{cf0}, \Sexpr{ocf[1]}, \Sexpr{ocf[2]}, \Sexpr{ocf[3]},
\Sexpr{ocf[4]}, \Sexpr{ocf[5]}.
\begin{answerlist}
  \item \$\Sexpr{wrongtvm}
  \item \$\Sexpr{notvm}
  \item \$\Sexpr{npv}
  \item \$\Sexpr{revtvm}
  \item \$\Sexpr{offnpv}
\end{answerlist}
\end{question}

\exname{Calculating NPV}
\extype{schoice}
\exsolution{00100}
\exshuffle{5}