#NumberAndAlgebra >[!info]- [Additive relations A | NSW Curriculum Website](https://curriculum.nsw.edu.au/learning-areas/mathematics/mathematics-k-10-2022/content/stage-3/faf843e1ab) >- MA3-AR-01 selects and applies appropriate strategies to solve addition and subtraction problems >[!abstract]- Prior Knowledge >- Additive Relations (Stage 2) ## Apply efficient mental and written strategies to solve addition and subtraction problems - Solve word problems, including multistep problems - Apply known strategies such as levelling, addition for subtraction, using constant difference, and bridging (Reasons about relations) - Use place value to add or subtract 3 or more numbers with different numbers of digits - Determine when it would be more efficient to use a calculator to add numbers - Identify efficient and inefficient multidigit subtraction strategies ## Use estimation and place value understanding to determine the reasonableness of solutions - Round numbers appropriately when obtaining estimates to numerical calculations - Use place value understanding to check for errors in calculations - Use estimation to check the reasonableness of solutions to addition and subtraction calculations