Solve real world problems with addition and subtraction within 1,000. Warm up with a Mystery Math Mistake as you add two 2-digit numbers using a decomposition strategy. Use visual models and place ...

Tom Meyvis is in the Leonard N. Stern School of Business, New York University, New York, New York 10012, USA. Heeyoung Yoon is in the Leonard N. Stern School of Business, New York University, New York ...