The correct answer is B, 8(9 + 3/4). The question asked for an expression that represents 8 times the sum of 9 and 3/4. The sum of 9 and 3/4 can be written as 9 + 3/4, and to multiply it by 8, we have to put it in parentheses. In PEMDAS (parentheses, exponents, multiplication and division, addition and subtraction) multiplication comes first, so if we left out the parentheses, we would be adding 72 to 3/4, since we multiply 8 and 9 first.
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