Hi

Sorry if this has already been addressed, but I coudn't find the topic anywere.

It looks like if you use the function `mean`

and set the `trim`

argument to a value greater than 0 inside `summarise`

, the output is the same as with the regular arithmetic mean.

If I take the `mpg`

column from the `mtcars data.frame`

and compute the two means separately I obtain this

```
mean(mtcars$mpg)
[1] 20.09062
mean(mtcars$mpg, trim = 0.3)
[1] 19.17857
```

Whereas if I do it with `summarise`

it gives this result

```
mtcars %>%
summarise(mpg = mean(mpg), mpg_trimmed = mean(mpg, trim = 0.3))
mpg mpg_trimmed
20.09062 20.09062
```

Am I doing something wrong? Is there something I'm not getting about how the trim argument works?

Thanks