Adding, Subtracting, Multiplying, and Dividing Multi-Digit Decimals Task Cards for 6th Grade Math Centers: These 24 task cards are aligned with Common Core Standard 6.NS.3: Add, Subtract, Multiply, and Divide Multi-Digit Decimals. Several different types of questions help you assess how well your students add, subtract, multiply, or divide multi-digit decimals using the standard algorithm. 6.NS.3. Fluently add, subtract, multiply, and divide multi-digit decimals using the standard algorithm fo