Question
I am an even number. When 1 is added to me and I am rounded off to the nearest ten, I become 780. When 1 is subtracted from me and I am rounded off to the nearest ten, I become 770. What number am I?
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I am an even number. When 1 is added to me and I am rounded off to the nearest ten, I become 780. When 1 is subtracted from me and I am rounded off to the nearest ten, I become 770. What number am I?