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Here are some tips for Estimated Addition, which aligns with Texas state standards:

Estimated Addition


For this topic, you need to know how to round numbers.
To review the Rounding Numbers topic, see here.

Estimation gives you an idea of what the actual answer is. Learning to estimate can help you add large numbers quickly.


Example:

536923
+ 32563
Estimate

Step 1:   Identify which place value you need to round to.
The largest place value of the number with the fewest digits is the place value to round to.

536923 has 6 digits and 32563 has 5 digits.
32563 has fewer digits and its largest place value is the ten-thousands.

Step 2:   Round the numbers to the correct place value found in Step 1.
We're rounding to the nearest ten-thousands.

536923 rounds to 540000.
  32563 rounds to   30000.

Step 3:   Add the rounded numbers to get the estimated sum.

540000
+ 30000
570000

The answer is

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