With more than three numbers, there can be many ways to do the addition. For example, with 4 numbers one of the ways is <math>2 + 3 + 4 + 5 = ((2 + 3) + 4 )+ 5 = (5 + 4 )+ 5 = 9+ 5 = 14</math>. | With more than three numbers, there can be many ways to do the addition. For example, with 4 numbers one of the ways is <math>2 + 3 + 4 + 5 = ((2 + 3) + 4 )+ 5 = (5 + 4 )+ 5 = 9+ 5 = 14</math>. |