Chapter 1 - Whole Numbers - 1.2 Adding Whole Numbers - 1.2 Exercises - Page 18: 24

Incorrect. Correct answer: 122

First, add the digits in the ones place. Since $7+5=12$, you have to "carry the one" to the tens place, and fill the ones place with the remainder, which is 2. When you add the digits in the tens place, you have to remember to also add the 1 that was carried over. $8+3+1=12$, so the final answer is 122. This does not match the answer that was given in the book.