class Faker::Bank

def compile_fraction(routing_num)
  prefix = (1..50).to_a.map(&:to_s).sample
  numerator = routing_num.split('')[5..8].join.to_i.to_s
  denominator = routing_num.split('')[0..4].join.to_i.to_s
  prefix + '-' + numerator + '/' + denominator
end