Traveling at 80% of his normal pace, a worker arrives 10 minutes tardy at his workplace. Determine the standard time he takes to get to the office.
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Answer: C. 40 minutes
Explanation
Traveling at eighty percent speed means the pace is four fifths of the normal rate. Reduced speed increases the journey duration to five fourths of the standard time. The extra time equals one quarter of the standard time, which equals ten minutes. Speed and time are inversely proportional when the travel distance remains strictly constant. A fractional drop in velocity results in a corresponding fractional increase in travel duration. Multiplying the extra time difference by four yields the original standard journey time.
Commuters use speed and time calculations to predict how traffic congestion impacts arrival schedules. Logistics companies analyze transit delays to optimize delivery routes and driver timetables. Physics problems involving constant acceleration often rely on these fundamental proportional relationships. Option A is too short and represents only half of the actual standard commute duration. Option B fails to properly account for the inverse proportionality between speed and time. Option D represents an incorrect calculation derived from adding the delay to the speed.
- Subject
- Mathematics
- Category
- Mathematics
- Topic
- —
- Difficulty
- medium
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