After a nowtorm, Frank and Julian are hired to clear the now from three identical driveway. Frank clear now from the firt driveway, while Juan take 30 minute longer to clear now from the econd driveway. Then Frank and Julian work together for 36 minute to clear the now from the third driveway. Both Frank and Julian work at a contant rate. How much time in minute did Frank take to clear now from the firt driveway?
