The difference between 81 and 3 = 81-3 = 78
their product = 81×3 = 243
their...quotient = 81÷3 = 27
The difference between 81 and 3 is added to the sum of their product and quotient.
Now we do the color coding:
78 is added to the sum of 243 and 27
the sum of 243 and 27 = 243+27 = 270
Now all it is is
78 is added to 270
and now it's easy: 78+270 = 348
Edwin