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I actually do have a problem with these types of pictures.
On one site math is never wrong isn't it? So the two equations in the middle just have to be wrong, we don't have any prblems and therefore the answer clearly should be 19!
On the other hand math is a totally made up construct made by us humans and even though it makes a lot of sence to us because we're use to it we just could define the axioms a diffrent way and if we assume that all these equations rely on the same axioms diffrent than those we're use to, than one possible answer also could be 96.