In a 300 m race, A beats B by 30 m or by 6 seconds. How long does A take to finish the race?
Answer & explanation
Correct answer: option 1
The correct answer is Option (1) → 54 seconds
“Beats by 30 m or by 6 seconds” means that B needs 6 more seconds to run the last 30 m after A finishes. So B’s speed is
\(30 \div 6 = 5\) m/s
B takes for the whole race
\(300 \div 5 = 60\) seconds
A finishes 6 seconds earlier:
\(60 - 6 = 54\) seconds
Why the other options are incorrect
Option (2) 56 seconds — Incorrect. A finishes 6 seconds before B’s 60 seconds, which gives 54 seconds.
Option (3) 60 seconds — Incorrect. This is B’s time for the race, not A’s.
Option (4) 66 seconds — Incorrect. This adds the 6 seconds to B’s time instead of subtracting it; A is the faster runner.