Question

Find the error in the student's calculation.

(2−4)5(3−8)
2(−2)∗5(6)
8(−2).26
−16−26
A. The student should have simplified the exponent first.
B. The student did not subtract 3 and 8 correctly.
C. The student should not have multiplied 8 and 2.
D. The student did not make an error.

Answer 1

The student made a mistake by not subtracting 3 and 8 correctly; the correct answer is −5, not 6, leading to an incorrect multiplication step and final answer.

Step-by-step explanation:

Let's find the error in the student's calculation. The original expression provided by the student is (2−4)5(3−8). The first step we would normally take is to simplify within the parentheses, which leads to −2 times 5 times −5. The student then proceeded to multiply 2 by −2, resulting in −4 and multiplied 5 by 6, which is not correct as 3 − 8 actually equals −5, not 6. The correct sequence should be −2 times 5 times −5, leading to −4 * −12, which equals −48, not 8(−2).26 as the student claims. Therefore, the correct answer is: B. The student did not subtract 3 and 8 correctly.