Boo-hoo. And I thought I was being clever😁 Well, it worked with 7th-graders as a reference point - many of them “knew” the length of the field of play. You probably realized, too, but couldn’t resist...😎 Regardless, the first down addition to the length of the field of play was apropos.
“American Football fields are rectangular playing fields with a required length of 120 yards (360’ | 109.75 m) and a width of 53.3 yards (160’ | 48.8 m). Based on yards, the field of play in a game of football refers to the 100 yards between the two opposing end zones on either side of the field at 10 yards | (30’ | 9.15 m) deep.”
https://www.dimensions.com/element/american-football-field
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