In his Christmas op-ed column (“Even total darkness can’t preclude us from seeing the light”), M.D. Harmon criticizes advertising agencies for letting errors “slip by” on “easily computed figures,” but he must think it’s OK for pundits to publish incorrect numbers.

He says the length of 146 football fields is about 8.3 miles, not 10 miles. He’s wrong. He forgot the end zones. A football field is 360 feet long. Line up 146 of these fields end to end and you get 52,560 feet, which is 9.95 miles. We can call that 10 miles.

Mr. Harmon also tells us that a “circle with a diameter of 60 miles encloses an area of nearly 11,310 square miles.”

Wrong again. A circle that size encloses an area of about 2,827 square miles. A circle with a radius of 60 miles encloses an area of nearly 11,310 square miles.

Brian Daly

Portland