Also, that's a great thing to point out but in the datasheet they recommend implementing a low pass filter. The error I made was going above the recommended 50kOhm resistor value! Thank you for bringing that to my attention.
If your problem is noise, you can try sample averaging. That will increase your signal to noise ratio. I definitely recommend at the very least to find the new equations using the experiment I did. That should help the most. :)