Let x1 x2 and x3 be independent random variables each

Question

Let X₁, X₂, and X₃ be independent random variables, each uniformly distributed on the interval ° to 1. Determine the number a such that

(i) Plat least one of the numbers X₁, X₂, X₃ is greater than a] = 0.9.

(ii) Plat least 2 of the numbers X₁, X₂, X₃ is greater than a] = 0.9.