Lets Start Sunday With A Brain Teaser

this math question appeared in the 1982 SAT Examination,

in case you are not from the US and wondering the SAT is, it is a standardized test widely used for college admissions in the United States, in the exam the questions give you about a minute to answer each one, but give yourself 5 minutes or so, but here is the thing, everyone got the question wrong! the video below explains the correct answer, 

but grab a coffee it is a long answer, amazing!