The problem is not 48/2*(9+3),
it is 48/2(9+3).
I put the problem in correctly. Google forced the issue and applied it’s logic. The result was shown.
However, I called in the big guns. My son has tutored Calculus, Chemistry and hard sciences at FSU for three years. He attended Emery Riddle in the 9th grade. I asked him to solve the problem. He gave a definitive 288 result.