UPSC Prelims 2012·CSAT·Quantitative Aptitude·Time, Speed and Distance

Mr. Kumar drives to work at an average speed of 48 km per hour. The time taken to cover the first 60% of the distance is 10 minutes more than the time taken to cover the remaining distance. How far is his office?

Dalvoy logo
Reviewed by Dalvoy
UPSC Civil Services preparation
Last updated 23 May 2026, 3:31 pm IST
  1. A30 km
  2. B40 kmCorrect
  3. C45 km
  4. D48 km

Explanation

To solve this problem, let the total distance to the office be D km. According to the question, the first 60 percent of the distance is 0.6D and the remaining 40 percent is 0.4D. The speed is given as 48 km per hour. Time is calculated as distance divided by speed. The time taken for the first part is 0.6D divided by 48. The time taken for the second part is 0.4D divided by 48. The difference between these two times is 10 minutes. Since the speed is in km per hour, we convert 10 minutes into hours by dividing by 60, which gives 10 divided by 60, or 1/6 hours. The equation becomes: 0.6D / 48 minus 0.4D / 48 equals 1 / 6 Subtracting the numerators: 0.2D / 48 equals 1 / 6 Multiply both sides by 48: 0.2D equals 48 / 6 0.2D equals 8 Solve for D: D equals 8 / 0.2 D equals 40 km Therefore, the office is 40 km away. The correct option is B.
Quantitative Aptitude: Mr. Kumar drives to work at an average speed of 48 km per hour. The time taken to cover the first 60% of the distance is
ShareWhatsAppXTelegram

Related questions

More UPSC Prelims practice from the same subject and topic.