in app/helpers/application_helper.rb [117:126]
def duration_in_words(finished_at, started_at)
if finished_at && started_at
interval_in_seconds = finished_at.to_i - started_at.to_i
elsif started_at
interval_in_seconds = Time.now.to_i - started_at.to_i
end
time_interval_in_words(interval_in_seconds)
end