What is the smallest integer that makes the difference x - (3/4 + 4/5) greater than 1? use estimation go find the answer, and then find the exact difference to show that your answer is correct

Acar started driving from city a to city b, distance between which is 620 miles, at a rate of 60 mph. two hours later a truck left city b and started moving towards city a at a rate of 40 mph. how many hours after the truck's departure will the two meet?