Single quote on float values

[marceloamp2]

I'm converting an array to an xlsx file, but I need the numeric string "100.50" to be converted to the number 100.50

As it is, it converts to 100.00 but Excel doesn't recognize it as a number and doesn't do the sum.

If I just change the (.) to (,) a single quote appears at the beginning of the number ('100,50) and it doesn't add up either.