CCLS - Math: 3.OA.9

Operations And Algebraic Thinking
Solve Problems Involving The Four Operations, And Identify And Explain Patterns In Arithmetic.
State Standard:
Identify arithmetic patterns (including patterns in the addition table or multiplication table), and explain them using properties of operations. For example, observe that 4 times a number is always even, and explain why 4 times a number can be decomposed into two equal addends.