Answer: 46,800
Your teacher may want you to erase the comma when inputting your answer.
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Step-by-step explanation:
Circle the digit in the hundreds place value, which is the digit 8. The next digit over is 2. This "2" is not five or larger, so we erase the "21" and replace it with "00".
The number 46,821 rounds to 46,800 which is the final answer.
Effectively, all we're doing is rounding the 821 to 800 and then sticking "46" in front. Notice how 821 is closer to 800 than it is to 900. So that's why we didn't round up to 46,900.