```ruby
class BingoBoard
  def initialize
    @board = Array.new(5) {Array.new(5.times.map{rand(1..100)})}
  end

  def ball_picker
    @bingo = "BINGO".chars
    @num = *(1..100)
    @ball = [@bingo.sample, @num.sample]
    p @ball
  end

  def checker
    @board.each do |sub_array|
      sub_array.map! do |num|
        p "num: #{num}"
        p "ball: #{@ball[1]}"
        if num == @ball[1]
          num = "X"
          print_board
        end
      end
    end
  end

  def print_board
    @board.each do |row|
      p row
    end
  end

end

print board = BingoBoard.new
5.times do
  board.ball_picker
  board.checker
end
```

Complete first iteration with working X
user
```ruby
class BingoBoard
  def initialize
    @board = Array.new(5) {Array.new(5.times.map{rand(1..100)})}
  end

  def ball_picker
    @bingo = "BINGO".chars
    @num = *(1..100)
    @ball = [@bingo.sample, @num.sample]
    p @ball
  end

  def checker
    @board.each do |sub_array|
      sub_array.map! do |num|
        if num == @ball[1]
          num = "X"
        else
          num
        end
      end
    end
    print_board
  end

  def print_board
    @board.each do |row|
      p row
    end
  end

end

board = BingoBoard.new
5.times do
  board.ball_picker
  board.checker
end
```
assistant