Answer:
1.2 hours
Explanation:
first im going to assume both travel at a constant speed the entire time
both motorboats travel 30 km, so emilio travels another 50 (80-30 = 50) km in 2 hours. speed = distance/time so the speed of the motorboats is 50/2 or 25km/h
divide 30 by 25 to get 1.2hours