Knitr Rmarkdown error object not found (from a previous question)

It's hard to trouble shoot this without a reproducible example, called a reprex and, in this case, a clearer description of the output you're looking for.

Taking a wild guess:

```{r, results="asis", echo = FALSE, warning=FALSE}
    Oak <- iris
    Oak.JH <- mtcars

`r nrow(Oak)/nrow(Oak.JH)`

should output 4.6875