Final answer:
To solve the proportion (n/4) = (28-7) / (12-14), you calculate each side to get (n/4) = 21 / (-2) and then cross-multiply to find n = -42. However, this solution does not match any of the provided options, suggesting there may be an error in the question or answer choices.
Step-by-step explanation:
The student asked to find the value of n in the given proportion (n/4) = (28-7) / (12-14). First, we need to calculate the values on the right side of the equation:
(28-7) = 21
(12-14) = -2
Thus, the proportion becomes:
(n/4) = 21 / (-2)
We then cross-multiply to solve for n:
4 * 21 = n * (-2)
84 = -2n
Divide by -2 to isolate n:
n = 84 / (-2)
n = -42
However, none of the options provided match the calculated value, indicating a potential error in the options or in the transcription of the problem. If this is the full and correct problem, none of the answer choices a-d are correct.