The rice actually only 'needs' a 1:1 ratio, but you need to put in extra to deal with evaporation; brown rice needs more-extra because it takes longer to cook (the bran slows absorption), and the longer cooking time leads to more evaporation.
TL;DR: ignore what's on the bag/box, and for every cup of rice add one cup of water (1:1, 2:2, 3:3), and then a fixed amount of extra overhead for evaporation.
Water-to-rice ratios are important. America's Test Kitchen has a good video on the topic, especially if you're using a pot and not a rice cooker:
* https://www.youtube.com/watch?v=JOOSikanIlI
* https://www.youtube.com/watch?v=DJFU7ezipbg
The rice actually only 'needs' a 1:1 ratio, but you need to put in extra to deal with evaporation; brown rice needs more-extra because it takes longer to cook (the bran slows absorption), and the longer cooking time leads to more evaporation.
TL;DR: ignore what's on the bag/box, and for every cup of rice add one cup of water (1:1, 2:2, 3:3), and then a fixed amount of extra overhead for evaporation.