Ruby Koans: Greed Dice Game

I was working on the Greed dice game in the Ruby Koans. My goal was to come up with an algorithm that was elegant, readable, and rubyesque. This is what I came up with:

def score(dice)
  score = 0
  points = Hash.new(0)
  points[1] = 100
  points[5] = 50
  
  counts = Hash.new(0)
  dice.each { |number| counts[number] += 1 }

  counts.each do |number, count|
    if count >= 3
      if number == 1
        score += 1000
      else
        score += (number * 100)
      end
      count = count - 3
    end
    
    score += points[number] * count
  end
  
  score
end

If you're not familiar with the ruby koans, here's the link to the path of enlightenment: Ruby koans