Explanation:

(0.6)^5/4 ÷ (0.36)^3/8 = (0.6)^5/4 ÷ (0.6)^{2 * 3/8} = (0.6)^5/4 ÷ (0.6)^3/4 = (0.6)^{5/4 – 3/4} = (0.6)^1/2
Similarly, (0.3)^13/12 ÷ (0.09)^7/24 = (0.3)^1/2
So (0.6)^1/2 × (0.3)^1/2 = (0.18)^1/2
So (0.18)^1/2 = (0.18)^1-x gives 1/2 = 1 – x,

So x = 1/2

Hence, option 2 is the correct answer.