output

[27] pry(#<User>)> solutions
=> [#<Solution id: 1, solution_url: nil, challenge_id: 1, user_id: 2, valid_solution: nil, created_at: "2013-01-19 14:51:04", updated_at: "2013-01-19 14:51:04", source: "Sample solution notes", title: "Some random title", language: "ruby", popularity: 2>]
[28] pry(#<User>)> solutions.inject { |sum, s| sum + s.up_votes.count }
=> #<Solution id: 1, solution_url: nil, challenge_id: 1, user_id: 2, valid_solution: nil, created_at: "2013-01-19 14:51:04", updated_at: "2013-01-19 14:51:04", source: "Sample solution notes", title: "Some random title", language: "ruby", popularity: 2>