In: Economics
3.4 Factor prices question
Imagine Bavis is producing economics degrees following production function q(L, K) = L^0.5 K^2. In the short run, capital is fixed at ̄K= 5. Bavis faces price p = 150 and can hire as many workers as it would like at a constant wage w = 75.
A. Find equilibrium labor (L∗) and wages.
B. What are Bavis’s profits at this equilibrium?
C. Prove that this profit level is a global maximum.
- Thank you!
a)
q = L0.5K2
K = 5
q = L0.5(5)2
Short run production function
q = 25L0.5
profit = pq - wL
= 150(25)L0.5 - 75L
= 3750L0.5 - 75L
d/dL = 3750(0.5)L0.5 - 1 - 75
d/dL = 1875 L- 0.5 - 75
put d/dL = 0
1875 L- 0.5 - 75 = 0
1875 L- 0.5 = 75
1875 = 75L0.5
L0.5 = 25
L* = 625
q = 25L0.5
= 25(625)0.5 = 625
b) Profit = pq - wL
= 625625 - 75625
= 390,625 - 46,875 = 343,750
c) Now
d/dL = 1875 L- 0.5 - 75
d2/dL2 = 1875(- 0.5)L- 0.5 - 1
= - 937.5 L- 1.5 < 0
Therefore Profit is maximum at L = 625