I will admit that on the first quick read, I thought "22% + 18% = 40%. Are they really just asking us to turn 40% into a fraction? That's shockingly easy!" So then, as I always do, I re-read with my skepticism radar on high alert. I then saw "partial results" and "Of those consumers who..." This was the big clue that they weren't asking for a percent of the whole; they were asking for a percent of a sub-group (this, by the way, happens often in overlapping sets).
A good moral: if a GMAT quant problem ever feels way too simple, it probably is! As I like to say, "there's no such thing as a ONE-MOVE answer."
Ceilidh Erickson
EdM in Mind, Brain, and Education
Harvard Graduate School of Education