The number '7' in the tens digit place will round up or down based on the value in the ones digit place. If the ones digit place is 5 or above, the tens digit rounds up. If the ones digit place is 4 or below, the tens digit remains the same, and rounds down. In the particular example, the ones digit is 5, so the tens digit will round up from '7' to '8'. Hence why the answer is 786,080.
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