Chapter 1

1.1 Number Patterns

pattern: is an ordered set of numbers or objects. The order helps you predict what will come next.

The pattern below shows shows subtracting 3 from every number.

Commutative Property of Addition : says that changing the order of addends does not change the sum.

Identity Property of Addition: for addition tells us that zero added to any number is the number itself.



1.2 Round to the Nearest Ten or Hundred

When you round a number, you find a number that tells you about how much or about how many.

1.3 Estimate Sums

1.5 Use Properties to add

Associative Property of Addition: (Grouping Property) the sum of three or more addends remains the same regardless of how the addends are grouped.

1.6 Use the break apart Strategy to add

1.7 Use Place Value to add

1.8 Estimate Differences

284 & 268 were both rounded to the nearest tens. The exact difference of 16 was close to the estimated difference of 20.

1.10 Use Place Value to Subtract

1.11 Combine Place Values to Subtract

1.12 Model Addition and Subtraction