by Chelsey Cooley Sat Oct 10, 2015 6:22 pm
'In last century' is unidiomatic and incorrect.
'Last century' without the 'in' is fine:
Last century, 1000 different flying vehicles were prototyped.
Something strikes me as odd about 'In the last century', but I can't quite put my finger on it. I think that this is technically fine:
In the last century, over 1000 different flying vehicles were prototyped.
Nonetheless, if you see both of them as answer choices in an SC problem, pick the first one, unless there are other issues with it. A good rule of thumb for concision is that if an identical meaning can be expressed in a significantly more succinct way, without introducing any other grammar problems, pick the more succinct answer choice. But concision is rarely the deciding issue on the GMAT.