Suppose that a company can produce 12,000 units when the number of hours of skilled labor y

Question:

Suppose that a company can produce 12,000 units when the number of hours of skilled labor y and unskilled labor x satisfy
384 = (x + 1)3/4(y + 2)1/3
Find the rate of change of skilled-labor hours with respect to unskilled-labor hours when x = 255 and y = 214. This can be used to approximate the change in skilled-labor hours required to maintain the same production level when unskilled-labor hours are increased by 1 hour.