Comparing ruby and clojure solutions - https://www.hackerrank.com/challenges/eval-ex

ex.clj

(dotimes [n (read-string (read-line))]
  (let [x (read-string (read-line))]
    (println
      (format "%.4f"
              (float (reduce (fn [m, i] (+ m (/ (reduce * (repeat i x))
                                                (reduce * (range 1 (inc i))))))
                             (int 1)
                             (range 1 10)))))))

ex.rb

gets.to_i.times do
  gets.to_f.instance_eval do
    puts((1..9).inject(1) { |m, i| m + self**i / (1..i).reduce(:*) }.round(4))
  end
end