After scoring a touchdown in football, the scoring team is entitled to either earn 1 extra point (by kicking the ball through goal posts) or 2 extra points (by advancing the ball past the goal line). Up until the 2016–2017 football season, teams who attempted to earn 1 extra point had a success rate of 0.993; teams who attempted to earn 2 extra points had a success rate of 0.480.
(a) Use the concept of expected value to explain why teams would typically go for 1 extra point.
(b) Use the concept of expected value to explain the justification in moving the snap for an extra point back to the 15-yard line after scoring a touchdown in professional football. The success rate of kicks where the snap is at the 15-yard line is 0.959.