How to display text after a formula?

Hi, I’m trying to display some text after a formula (in the same cell) in Writer.

I can get the formula to work ok on its own, as soon as I try to add text,
it doesn’t display the text and it also breaks the formula

Any advice?

Using LibreOffice version on ubuntu 14.10

One way, adding the text in the cell number format.

Sample file

but seems not too much safe, editing the text directly in cell not in the number format, converts the formula to text.