123 plus 88 equals 211
456 + 789 + 123 + 123456789 = 123458157
123
1,234,568,013
111111111111111111111234
126
123 + 56 = 179 - 97 = 82
444
123
3 x 124 = 372
5x + 17 = 7x - 123 123 + 17 = 7x - 5x 140 = 2x x = 140 ÷ 2 x = 70
The answer is 20. In each addition, the individual digits are added together (1+2+3+5+4 = 15)