Both answers are right it just depends how you solve the question, OP's is the top if you remember that the symbol on applies the the number directly after it and no more, those with the answer 2 are solving the equation on the bottom. (Sorry for badly formatted equations but you get the idea and I can't be fucked using a program to make them look nice and uploading a screencap)
It's not necessarily poorly written, but writing it as below would eliminate the chance of confusion between answers. Beside where do you ever see somebody write a complex math equation with a division symbol.
48
------- (9+3) = 288
2
48
------------- = 2
2 (9+3)