You need to write this question out in algebra form first. X + x + 1 + x + 2 = 72 than you add the like terms
3x + 3 = 72 ... 3x=69 ... x=69/3 ... x=23. So we have now found x now you just add 1 to x and get 24 and you add 2 to x you will get 25.
Add 23 + 24 + 25 together you will get 72
