swerve wrote:When running a mile during a recent track meet, Nuria was initially credited with a final time of 5 minutes, 44 seconds. Shortly after her run, officials realized that the timing mechanism malfunctioned. The stopwatch did not begin timing her until 11/25 of a minute after she began to run. If the time was otherwise correct, how long did it actually take Nuria to run the mile?
A. 5 minutes, 17.6 seconds
B. 5 minutes, 21.8 seconds
C. 5 minutes, 43.56 seconds
D. 5 minutes, 44.44 seconds
E. 6 minutes, 10.4 seconds
The OA is E
Source: Veritas Prep
The
long approach is to meticulously convert 11/25 of a minute to seconds, and then ADD that unaccounted time to Nuria's recorded time (of 5 minutes, 44 seconds)
However, when we check the answer choices before performing any calculations (
ALWAYS check the answer choices before performing any calculations), we see that most answers are LESS THAN 5 minutes, 44 seconds
So, we can already ELIMINATE A, B and C
Now recognize that 1/3 of a minute = 20 seconds, and if we add 20 seconds to 5 minutes, 44 seconds, we can MORE than 6 minutes.
Since 11/25 is greater than 1/3, the final sum will be MORE than 6 minutes.
Only answer choice E is greater than 6 minutes, so it must be the correct answer.
Cheers,
Brent
Brent Hanneson - Creator of GMATPrepNow.com
