Subject: General Aptitude · Chapter: Time and Distance · Exam: 2005 · Marks: · Difficulty:
An aeroplane first flew with a speed of 440 kmph and covered a certain distance. It still had to cover 770 km less than what it had already covered, but it flew with a speed of 660 kmph. The average speed for the entire flight was 500 kmph. Find the total distance covered.
(a)1375 km
(b)2750 km
(c)3250 km
(d)4400 km
Answer
Answer (as printed): B
Explanation
Let the distance covered at 440 kmph be $x$ km. Then, distance covered at 660 kmph = ( $x-770$ ) km. Total distance covered $=(x+x-770) \mathrm{km}$ $$=(2 x-770) \mathrm{km} .$$ Hence, total distance covered $=(2 x-770)$ $$=(2 \times 1760-770) \mathrm{km}=2750 \mathrm{km} .$$