In my thinking:
- 3 times a is increased by b:
This is a SVO sentence. The subject is "3 times a", the verb is "is increased" and the object is "by b". Therefore the correct form in math is 3a+b
- 3 times a increased by b:
This is a shorten form of "3 times a, which is increased by b". The subject is "3", the verb is "times" and the object is "a increased by 3" or "a, which is increased by 3". Mathematically, it is 3(a+b)
But my teacher and the rest of my GRE class don't agree with this. They opine that these sentences are the same, and the correct is 3a+b. What do you think?
This is the origin question:
When 3 times a number n is increased by 7, the result is at most 4 times the number decreased by 1