What rules should you follow when adding and subtracting? Check all that apply.

For addition and subtraction in scientific notation, first make the exponents the same so the leading numbers represent quantities at the same scale; then add or subtract those leading numbers. The result is rounded to the least precise decimal place, not to the fewest significant figures. Therefore, the applicable rules are that the exponents must match and that the result has the same number of decimal places as the least precise number.

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