Mathematics
NULL
Medium
Question
A car traveling at 5/7 of its actual speed covers 42 km in 1 hr 40 min 48 sec. What is its actual speed?
A
30 km/hr
B
35 km/hr
✓ Official correct answer
C
25 km/hr
D
40 km/hr
Community credibility
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A
30 km/hr
No member explanations yet for this option.
B
35 km/hr
No member explanations yet for this option.
C
25 km/hr
No member explanations yet for this option.
D
40 km/hr
No member explanations yet for this option.
Explanation
Time = 1 + 40/60 + 48/3600 = 126/75 hours. Speed at 5/7 of actual = 42 ÷ (126/75) = 25 km/h. Actual = 25 × 7/5 = 35 km/h.