```{r data generation, echo = FALSE, results = "hide"}
cf0 <- sample(10:16, 1) * -100
ocf <- sample(seq(225, 550, 25), 5)

npvfunc <- function(r) {
  discounts <- sapply(1:5, function(i) (1 + r) ** i)
  npv <- (sum(ocf / discounts) + cf0) ** 2
  return(npv)
}

res <- optimize(npvfunc, interval = c(-1,1))

irr <- round(res$minimum, 4) * 100.0

wrong1 <- irr + sample(c(1.0, -1.0), 1)
wrong2 <- irr + sample(c(0.25, -0.25), 1)
wrong3 <- irr + sample(c(0.5, -0.5), 1)
wrong4 <- irr + sample(c(0.75, -0.75), 1)
```

Question
========
Find the internal rate of return of a project with the following cash flows,
starting at time 0: \$`r cf0`, `r ocf[1]`, `r ocf[2]`, `r ocf[3]`, `r ocf[4]`, `r ocf[5]`.

Questionlist
------------
* \$`r wrong1`
* \$`r wrong2`
* \$`r irr`
* \$`r wrong3`
* \$`r wrong4`

Meta-information
================
exname: Calculating IRR
extype: schoice
exsolution: 00100
exshuffle: 5