During periods of bad weather, as compared with periods of clear weather, how many additional gallons of fuel on average should FreeEx expect its planes to consume because of airport congestion?

the question is incomplete:

λ = 20

μ₀ = 30

μ₁ = 60

Ls for good weather = 20 / (60 - 20) = 20/40 = 0.5

Ls for bad weather = 20 / (30 - 20) = 20/10 = 2

Ws for good weather = 60 / 40 = 1.5

Ws for bad weather = 60 / 10 = 6

Wg for good weather = 1.5 - (60 / 60) = 1.5 - 1 = 0.5

Wg for bad weather = 6 - (60 / 30) = 6 - 2 = 4

Fuel consumed due to slack:

good weather = Ws x λ = 1.5 x 20 = 30 gallons

bad weather = Ws x λ = 6 x 20 = 120 gallons

So each plane should expect to consume 120 - 30 = 90 additional gallons of fuel due to bad weather

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