Skill: Add 100 to a number

Explanation and Free Practice Resources

Adding 100 means increasing the hundreds value by one while preserving the tens and ones digits; for numbers below 100, it creates the corresponding number one hundred greater. Within whole numbers through 1,000, this relationship can be represented with place-value notation or a number line, including cases such as 900 + 100 = 1,000; decimals, negative numbers, and more general extensions are not included.

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Detailed Explanation: Add 100 to a number

Adding $100$ means making the hundreds digit one greater. The tens and ones digits stay the same.

Example: Find $346+100$ .

Look at the hundreds digit in $346$ . It is $3$ .
Add $1$ to the hundreds digit: $3+1=4$ .
Keep the tens digit ( $4$ ) and ones digit ( $6$ ) unchanged.

So,

346+100=446

The number becomes $100$ greater because only the hundreds place changes.

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Addition - Whole Number - Add 100 to a Number

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