Aresearcher wishes to compare how students at two different schools perform on a math test. he randomly selects 40 students form each of the schools and obtains their test scores. he pairs the first score from school a with the first score from school b, the second score from school a with the second score from school b and so on. he then performs a hypothesis test for matched pairs.

a.) is this approach valid? why or why not

b.) if it is not a valid approach, how should the researcher have proceeded?