Which method below could provide an estimate for the number of mailboxes in a neighborhood a: n = number of mailboxes on one street x number of streets in the neighborhood b: n = number of mailboxes on one street / number of streets in the neighborhood c: n = number of mailboxes in the neighborhood / number of streets in the neighborhood d: n= number of mailboxes in the neighborhood x number of streets in the neighborhood

Given the choices, we have that we need to extrapolate data from one street to the whole neighborhood. If we know that there are y mailboxes in one street, then to account for the mailboxes in all streets, we need to multiply by the number of streets. Hence, the correct answer is A. B and C are wrong because they give a ratio rather than a total amount while the formula in D involves the quantity we want to find (number of boxes in the neighborhood).