Rounding Numbers

Main Learning Goal and Core Concepts: The goal of the lesson is to understand how to round numbers. Students will primarily focus on understanding when they need to round numbers and at what position.

Vocabulary

Rounding

Rounding is replacing a number with a value in an estimate form.

Place Value

Place value is the value of each digit in a number.

Lesson Brief

Steps to rounding numbers:

  1. Underline what place value the number needs to be rounded.
  2. Look at the place value and determine if it needs to be rounded up or down.
    1. 5 or more, raise the score. This means if the value to the right of the number is 5 or greater, you would round the number up by 1 value.
    2. 4 or less, let it rest. This means if the value to the right of the number is 4 or less, then no rounding needs to be done.
  3. After rounding, the rest of the values after the place value are 0.

Example: 

Round the following number to the nearest thousand:

1,539

  1. Read the directions on what place value the number needs to be rounded. 

The directions ask to round to the nearest thousand, meaning the thousand place will be looked at. In this case, the 1 in 1,539 is in the thousands place. 

 

  1. Look at the place value and determine if it needs to be rounded up or down.

To determine if the place value, 1, needs to be rounded up or down, the next number is observed. The number next to the thousands place is 5 in 1,539. The number is 5 which means the 1 in 1,539 should be rounded to 2.

 

  1. After rounding, the rest of the values after the place value are 0.

The rounded number should be 2,000.

Notes:

  • If the value is 9 and needs to be rounded up, then the value to the left will be rounded up and the rest of the values are 0.
  • All the values after the underlined place value become a 0.

For more information regarding rounding numbers, consider the link here.

The blank worksheet and its corresponding answer key are below:

Rounding Numbers Blank Worksheet

Rounding Numbers Worksheet Answer Key