Section 1
📘 Rounding
New Concept
To round a number to the nearest ten, we choose the closest number that ends in zero.
What’s next
Next, you’ll practice rounding numbers to the nearest ten and money to the nearest dollar and quarter.
In this Grade 4 Saxon Math lesson from Chapter 2, students learn how to round whole numbers to the nearest ten and money amounts to the nearest dollar and nearest 25 cents. The lesson uses number lines to visualize how to identify the closest multiple of ten and applies the rule that numbers exactly halfway between two tens round up. Students also practice distinguishing between exact and rounded amounts in real-world contexts.
Section 1
📘 Rounding
To round a number to the nearest ten, we choose the closest number that ends in zero.
Next, you’ll practice rounding numbers to the nearest ten and money to the nearest dollar and quarter.
Section 2
Rounding to the Nearest Ten
To round a number to the nearest ten, we choose the closest number that ends in zero.
For example, is closer to than , so it rounds to . The number is closer to . A number like is exactly halfway, so it rounds up to .
Think of it like jumping to the nearest safety platform on a number line, where platforms are numbers like . If you're exactly halfway between two, the rule is to always jump up!
Section 3
Rounding to the Nearest Dollar
To round money amounts to the nearest dollar, we round up if the number of cents is or more. We round down if the number of cents is less than .
An item costing dollars rounds down to dollars. An item costing dollars rounds up to dollars.
Is the change cents or more? You're closer to the next dollar, so round up! If it's cents or less, you're closer to the dollar you already have, so round down.
Section 4
Math Language
We often use rounded amounts instead of exact amounts because they are easier to work with and to understand.
It's easier to say 'about people attended' instead of ' people'. It also helps quickly estimate a shopping total.
Why round? It's a mental shortcut that makes numbers clean and simple. Saying 'about 70 dollars' is much quicker for our brains to process and use in calculations than a clunky number like ' dollars'.
Book overview
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Section 1
📘 Rounding
To round a number to the nearest ten, we choose the closest number that ends in zero.
Next, you’ll practice rounding numbers to the nearest ten and money to the nearest dollar and quarter.
Section 2
Rounding to the Nearest Ten
To round a number to the nearest ten, we choose the closest number that ends in zero.
For example, is closer to than , so it rounds to . The number is closer to . A number like is exactly halfway, so it rounds up to .
Think of it like jumping to the nearest safety platform on a number line, where platforms are numbers like . If you're exactly halfway between two, the rule is to always jump up!
Section 3
Rounding to the Nearest Dollar
To round money amounts to the nearest dollar, we round up if the number of cents is or more. We round down if the number of cents is less than .
An item costing dollars rounds down to dollars. An item costing dollars rounds up to dollars.
Is the change cents or more? You're closer to the next dollar, so round up! If it's cents or less, you're closer to the dollar you already have, so round down.
Section 4
Math Language
We often use rounded amounts instead of exact amounts because they are easier to work with and to understand.
It's easier to say 'about people attended' instead of ' people'. It also helps quickly estimate a shopping total.
Why round? It's a mental shortcut that makes numbers clean and simple. Saying 'about 70 dollars' is much quicker for our brains to process and use in calculations than a clunky number like ' dollars'.
Book overview
Jump across lessons in the current chapter without opening the full course modal.
Continue this chapter