This question can be solved using 2 equations since there are 2 unknowns. First, let x = price of the tennis ball and y = price of the baseball. The resulting equations are: (1) 5x +3y = 23.75 and (2) 2x + 7y = 31.25. Solving the 2 equations simultaneously, you get, x = 2.5 and y = 3.75. The price of the baseball is then $3.75.