Multiple choice

The sum of the length of the train is 660. and ratio of their speed is 5 : 8. and ratio of time taken to cross an electric pole is 4 : 3. find the difference between their length ?

  1. $50$
  2. $78$
  3. $64$
  4. $60$
  5. $None of these$
Reveal answer Fill a bubble to check yourself
D Correct answer
Explanation

Speed ratio 5:8, time ratio 4:3. Distance = Speed × Time. Length1 = 5k×4t = 20kt. Length2 = 8k×3t = 24kt. Sum of lengths: 20kt+24kt=44kt=660, so kt=15. Difference in lengths: 24kt-20kt=4kt=4×15=60. The answer is 60.