Answer:
D. 8 2/3
Explanation:
(5 3/4) + (2 11/12) = (5 +2) + (3/4 +11/12)
... = 7 + (9/12 +11/12)
... = 7 + 20/12 = 7 + (1 8/12)
... = 8 8/12 = 8 2/3
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Comment on math symbols
The caret (^) signifies exponentiation. your number 5^3/4 = (5^3)/4 = 125/4 = 31.25. This is not the mixed number you apparently intend.
A mixed number is customarily written with a space between the integer and the fraction. In an expression, this can be confusing, so I generally put parentheses around a mixed number that is part of an expression.