Answer:
d. 42.90 hours
Step-by-step explanation:
y = aQᵇ
y = average time to produce one more unit
a = the time it took to produce the first unit
Q = cumulative production
b = learning rate = [(log learning rate in %) / log 2] = -0.152003093
learning rate in % = 10.8 / 12 = 0.9 = 90%
cumulative quantity average hours per unit total hours
1 12 12
2 10.8 22.8
3 10.38 33.18
4 12 x 4⁻⁰°¹⁵²⁰⁰³⁰⁹³ = 9.72 42.90