Mathematics
NULL
Medium
Question
In a race a car went at 150 km/h. At 180 km/h it would have finished 3 minutes earlier. Find the track length.
A
50 km
B
45 km
✓ Official correct answer
C
40 km
D
30 km
Community credibility
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A
50 km
No member explanations yet for this option.
B
45 km
No member explanations yet for this option.
C
40 km
No member explanations yet for this option.
D
30 km
No member explanations yet for this option.
Explanation
Time difference: d/150 − d/180 = 3/60 ⇒ 30d/(150×180) = 1/20 ⇒ d/900 = 1/20 ⇒ d = 45 km.