Add every digit, keep the last one
Add up every digit of the packet amount, including both decimals, then keep only the ones digit. For 3.42 that is 3+4+2=9, so nine points.
If the sum is exactly 10, or ends in 0, it counts as 10 points — NiuNiu, the highest point value. For 6.04 that is 6+0+4=10, so NiuNiu.