coins_controller.rb

 @coins.each do |c|
      #c.cur_name
      cur = []
      @coin_cur = Coin.where(:cur_name => c.cur_name).last
      @coin_10 = Coin.where(:cur_name => c.cur_name).where("date <?", 10.minutes.ago)[-3]
      @coin_20 = Coin.where(:cur_name => c.cur_name).where("date <?", 20.minutes.ago)[-5]

      if @coin_cur.price.present?
        #binding.pry
        dif10 = ((@coin_cur.price/@coin_10.price)*100)-100
        dif20 = ((@coin_cur.price/@coin_10.price)*100)-100
        @results[c.cur_name] = {"volume"=>c.volume24, "price"=>c.price,
                                '10'=>dif10,'20'=>dif20,
                                'price_now'=>@coin_cur.price, 'price_10'=>@coin_10.price
                                }
      end