284 rounded to the nearest 10 is: 280
because...
If we want to round 284 to the nearest 10 you will have to check the last digit. If the last digit of 284 is 5 or greater than 5, you will have to move it forward. However, if the last digit is less than 5 then that means you will have to move backward. So in this case, 4 is the last digit of "284", 4 is less than 5 so we have to move backward, which results to our answer which is 280
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