Skill: Subtract a number from itself

Explanation and Free Practice Resources

Subtracting a whole number from an equal whole number gives a difference of zero: 8 − 8 = 0 and 245 − 245 = 0. The meaning is that removing every unit in one quantity from an equal quantity leaves nothing; on a number line, the subtraction represents a distance of zero. This applies to nonnegative whole numbers within the usual range through 1,000, not to negative numbers or fractions.

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Detailed Explanation: Subtract a number from itself

When you subtract a number from the same number, you take away every unit. Nothing is left, so the answer is always $0$ .

Example: Find $245 - 245$ .

Notice that both numbers are the same: $245$ and $245$ .
Subtract all $245$ units from the first group of $245$ units.
No units remain.

Therefore,

245 - 245 = 0

You can also think of it as starting at $245$ on a number line and moving back $245$ spaces. You land at $0$ .

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Subtraction - Whole Number - Subtract from Self 1 digit

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