let x = the amount taken in for Sunday games
x - 139.50 = the amount taken in for Friday games
x + (x - 139.50) = 3428.50
2x - 139.50 = 3428.50
2x = 3568
x = 1784
Sunday games earn $1784, and Friday games earn 1784 - 139.50 = $1644.50