Incorrect decimal values read after using multiplier 0.1

Hi
I am reading a signed integer from a PLC via a serial port
The pls does not give out data as float so using signed integer.
Value that should be read as 28.2 is can be read from the PLC as 282.
Hence the multiplier is set to 0.1 to decipher the data correctly.
After the multiplier ScadaBR reads the value as 28.200000000000003
Without the multiplier the data was read correctly as 282

How to read data as only 28.2 , ie only one decimal place

Also how to use script to divide by to if name of Point is Temp1
How to export data to a csv with time , reading1 , reading2 etc
Also need to trigger to export data/report once value crosses some threshold.

Look forward to some solutions.

Further to the above message , the below link has been great and helped me address most of the questions
https://www.egnite.de/support-en/tutorials/tutorial-querx-and-scadabr/