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Suppose the Sun’s light contains a blue wavelength of 450 nm and a red wavelength of 650 nm. Rayleigh scattering tells us that the scattering intensity I is inversely proportional to the fourth power of the wavelength: I ∝ 1/λ⁴. To find the ratio of blue to red scattering: 1. Write the formula for the ratio: I_blue / I_red = (λ_red / λ_blue)⁴. 2. Plug in the numbers: λ_red = 650 nm, λ_blue = 450 nm. 3. Compute λ_red / λ_blue = 650 / 450 ≈ 1.444. 4. Raise this ratio to the fourth power: (1.444)⁴ ≈ 4.34. 5. Interpretation: Blue light scatters about 4.3 times more than red light under the same conditions. That’s why the sky is blue during the day and why red dominates at sunrise/sunset when blue has been scattered away. So, by using the simple 1/λ⁴ relationship, we can see how much more blue light gets scattered compared to red light.