To simplify the expression \( \frac{2 \cdot 3 \cdot (-4)}{5 \cdot (-2)} \), we can first rewrite it without the negative signs affecting the clarity, then we can proceed with the calculation.
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Rewrite the expression without sign confusion: \[ \frac{2 \cdot 3 \cdot 4}{5 \cdot 2} = \frac{6 \cdot 4}{5 \cdot (-2)} \]
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Calculate the numerator and denominator: \[ \text{Numerator: } 2 \cdot 3 \cdot 4 = 24 \] \[ \text{Denominator: } 5 \cdot (-2) = -10 \]
So, we can express the division: \[ \frac{24}{-10} = -\frac{12}{5}\text{ if simplified.} \]
Now let's evaluate the students' answers to check who is correct:
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Adam: \[ \frac{2 \cdot 5(2)}{3 \cdot 4} \quad \text{This is incorrect.} \]
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Nick: \[ \frac{5(2)}{2 \cdot 3(4)} \quad \text{This is incorrect.} \]
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Shane: \[ \frac{2 \cdot 3(4)}{5(2)} \quad \text{This is also incorrect.} \]
As none of the students produced the equivalent simplified expression of \( -\frac{12}{5} \), the correct response to choose would be:
None of these are correct because the students did not add the exponents in the numerator and then subtract exponents since there is division.