Question

A plane flew from Sky City airport to the Plainsville airport at 800 km/h and then returned to Sky City at 900 km/h. The return rip took 30 minutes less than the flight to Plainsville. How far apart are the airports?

Answer 1

3,600 Km

Explanation:

s = d/t. d = st

s = speed, d = distance traveled, t = time elapsed

d = 800t and d = 900 (t - 30)

d = d

800t = 900 (t - 30)

800t = 900t - 27000

27000 = 900t - 800t

27000/100 = t

270 min = t

270/60 = 4.5 hours

800 km * 4.5 hours = 3,600 Km

900 km * (4.5 - 0.5) = 3,600 Km