Multiple choice

A man covers first $120$ km of his journey at $40$ km/hr, next $145$ km at $58$ km/hr and last $35$ km half an hour Find his average speed during the whole journey.

  1. $20$ km/hr
  2. $30$ km/hr
  3. $40$ km/hr
  4. $50$ km/hr
Reveal answer Fill a bubble to check yourself
D Correct answer
Explanation

Total distance = 120 + 145 + 35 = 300 km. Time 1 = 120/40 = 3 hrs. Time 2 = 145/58 = 2.5 hrs. Time 3 = 0.5 hrs. Total time = 3 + 2.5 + 0.5 = 6 hrs. Average speed = 300 / 6 = 50 km/hr.

AI explanation

Average speed is calculated as total distance divided by total time. The total distance is 120 km plus 145 km plus 35 km, which is 300 km. The times for each segment are 120 divided by 40 (3 hours), 145 divided by 58 (2.5 hours), and half an hour, summing to a total time of 6 hours. The average speed is 300 km divided by 6 hours, which equals 50 km/hr.

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