Final answer:
To find the number of professors of each rank that are needed, a method involving matrix inversion can be used. The system of equations representing the teaching, grading, and committee work hours can be written in matrix form and solved using the inverse of the coefficient matrix.
Step-by-step explanation:
To find the number of professors of each rank needed, we can set up a system of equations using matrix inversion. Let's define the variables:
- F = number of full professors
- A = number of associate professors
- As = number of assistant professors
The given information can be represented by the following equations:
- Teaching hours: 6F + 9A + 12As = 7
- Grading hours: 8F + 12A + 15As = G
- Committee work hours: 4F + 3A + As = C
Using matrix inversion, we can write the equations in matrix form:
[6 9 12][F A As] = [7 G C]
To solve for F, A, and As, we can multiply both sides by the inverse of the coefficient matrix:
[F A As] = [6 9 12]^-1 [7 G C]
Once we have the inverse of the coefficient matrix, we can substitute in the values for 7, G, and C to find the values of F, A, and As.