Answer:
D. 720 kmph
Explanation:
Distance = rate • time.
First, we must find the distance covered when the airplane flies 240 km/hr in 5 hours.
D = 240 • 5
D = 1200 km.
Now the question is asking us, to travel 1200 km in 1 2/3 or 5/3 hours, how fast must we travel at? We can use the same equation, except this time we know the distance and the time, we need to solve for the rate.
1200 = r • 5/3
1200 ÷ (5/3) = r
1200 ÷ 5/3 = 1200 • 3/5 = 0.6 • 1200 = 720.
Therefore, the airplane must travel at a speed of 720 kilometers per hour.