The learner identifies the immediate predecessor of a whole number within 1–120, understanding that the number before it is one less and is located one step to the left on a number line; this includes transitions such as 20 to 19 and 100 to 99, with 0 recognized as preceding 1. The understanding supports counting, subtraction, and place-value reasoning; negative numbers, fractions, and generalized predecessor rules for arbitrary integers are not included.
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- Learn “Identify the number before” with a detailed explanation of the concept
- Master “Identify the number before” with unlimited, free practice problems
- Download (or modify) a free worksheet on Identify the number before you can use at home or in class with practice problems that scaffold and explore “Identify the number before” from different perspectives.
- Start working on adaptive units like “Number Sense - Basics” or “Number Sense - Intro” that introduce, teach, or practice “Identify the number before” to maximize your learning.
Detailed Explanation: Identify the number before
To find the number before a number, move one step to the left on a number line. The number before is also one less.
Example: What number comes before ?
- Start at .
- Count back one: .
- .
So, the number before is .
Remember: the number before is .
Learn by doing: Identify the number before
Click a topic below to practice the foundational skills you'll need, learn the steps, or master this skill
Your results
Practice with unlimited practice problems
Practice:
Number Chart to 100 - Next/Previous Number (one, below 100)
Earned ?
Download/Modify Free Grade 1 'Identify the number before' Worksheet
Print this free 'Identify the number before' worksheet to practice this skill away from the computer. Click 'Modify' to easily customize this worksheet to your exact needs.
This Worksheet Includes:
- Number Chart to 100 - Next/Previous Number (one, below 100)
- Subtraction - Whole Number - Subtract 1 - Columns
- Subtraction - Whole Number - Subtract 1
- Count Backwards by 1s - Within 100
- Number Chart to 100 - Next/Previous Number (one, below 70)
- Number Chart to 100 - Next/Previous Number (one, below 50)
- Number Chart to 100 - Next/Previous Number (one, below 20)
- Count Backwards by 1s - Within 20
Units Teaching This Skill
These adaptive units introduce, teach, or reinforce this skill (Identify the number before) through scaffolded problems that grow in difficulty as concepts are understood.