2022 · Q34
In a flight of 2800 km, an aircraft was slowed down due to bad weather. Its average speed for the trip was reduced by 100 km/hr and time of flight increased by 30 minutes. What was the original average speed of the aircraft?
Elementary MathematicsTime, Speed and Distance
- A700 km/hr
- B750 km/hr
- C800 km/hr
- D900 km/hr
Explanation
2800/(v−100) − 2800/v = 0.5. Trying v = 800: 4 − 3.5 = 0.5, which satisfies the equation, so the original speed was 800 km/h. The keyed option is C.