Ohio Mathematics Academic Content Standards (2001)
Number, Number Sense and Operations Standard
Use relationships between operations, such as subtraction as the inverse of addition and division as the inverse of multiplication.
Grade Level Indicators (Grade 3)
Explain and use relationships between operations, such as:
a. relate addition and subtraction as inverse operations;
b. relate multiplication and division as inverse operations;
c. relate addition to multiplication (repeated addition);
d. relate subtraction to division (repeated subtraction).
Add and subtract whole numbers with and without regrouping.
Grade Level Indicators (Grade 4)
Demonstrate fluency in adding and subtracting whole numbers and in multiplying and dividing whole numbers by 1- and 2-digit numbers and multiples of ten.
Principles and Standards for School Mathematics
Number and Operations Standard
Compute fluently and make reasonable estimates
develop fluency in adding, subtracting, multiplying, and dividing whole numbers;