To get the answer, you need to think of it like a see-saw.
Both sides must equal the same relative to 33.5. For example, 32 is 1.5 away from 33.5 so you could say you have 1.5*4 (because theres 4 tubes with 32 sweets). If you were to do this for the whole table, it would look something like this:

This simplifies to:




This method can sometimes be inefficient depending on how many values but is probably the simplest way to solve this problem.
hope this helps :)
(sorry the other way is kinda hard to explain possibly ask your teacher tomorrow)
The answer is 2900mg because you have to divide the two numders
I believe that the answer is 300
Depends is the positive integer is larger than the negative interger for example -10+5=-5.
10+-4=6