Solution: Kth Smallest Prime Fraction

Statement

You are given a sorted array of unique integers, arr, which includes the number $1$ and other prime numbers. You are also given an integer $k$.

For every index $i$ and $j$ where $0 \leq i < j <$ arr.length, you can form a fraction by taking the number at index $i$ as the numerator and the number at index $j$ as the denominator, resulting in the fraction arr[i] / arr[j].

Your task is to return the $k^{th}$ ...