The speaker multiplies, divides, adds, and subtracts the numbers in his story to capture the size and scope of the family history. The speaker’s grandfather lived for 25 years before his right to vote was protected by law, meaning there were several years when he was old enough to vote but couldn’t. The grandfather is still alive as the speaker tells this story, making this fact all the more immediate. His grandfather was also “two / decades younger than the president / who signed the paper that made it so” (Lines 2-4). This figure invokes the troubling reminder that so many politicians and presidents before him failed to protect this right in their long careers. The speaker also emphasizes the smallness of his grandparents’ homes by dividing the number of bedrooms among the children: there were “half as many” (Line 12), which implies that they could have used at least double of what they had.

Some of the calculations in the poem aren’t precisely accurate. The speaker is likely exaggerating when he says his head was “five times too big” (Line 23). The point here is to convey that his head was indeed big, and that, to him, it is comically huge.