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
When running a mile during a recent track meet, Nuria was
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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)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
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
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\[? = 5\min 44{\text{s}} + \frac{{11}}{{25}}\min\]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
Source: Veritas Prep
\[\frac{{11}}{{25}}\min \,\,\left( {\frac{{60{\text{s}}}}{{1\min }}} \right)\,\,\, = \,\,\,\frac{{11 \cdot 12}}{5}{\text{s}}\,\,\,\mathop = \limits^{\left( * \right)} \,\,\,26\frac{2}{5}{\text{s}}\]
\[\left( * \right)\,\,\,\frac{{\left( {10 + 1} \right) \cdot 12}}{5} = \underleftrightarrow {2 \cdot 12 + \frac{{12}}{5} = 24 + \frac{{10 + 2}}{5}} = 26\frac{2}{5}{\text{s}}\]
\[? = 5\min 44s + 16s + 10s + \frac{2}{5}s = 6\min 10.4\,{\text{s}}\]
The above follows the notations and rationale taught in the GMATH method.
Regards,
Fabio.
P.S.: the alternative choices DO help you avoid the precise calculations above, but with proper (and very useful) tools those calculations are easy!
Fabio Skilnik :: GMATH method creator ( Math for the GMAT)
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Hi All,
We're told that 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? Based on the 'spread' of the answer choices, you can actually answer this question with almost no math at all; paying attention to the information that you're given - along with a little logic - can get you the correct answer rather quickly.
We know that Nuria was timed at 5 minutes 44 seconds, but the stop watch was NOT started until almost HALF OF A MINUTE had gone by. Thus, Nuria's actual time is greater than 5 minutes 44 second - almost HALF A MINUTE greater. There's only one answer that makes sense...
Final Answer: E
GMAT assassins aren't born, they're made,
Rich
We're told that 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? Based on the 'spread' of the answer choices, you can actually answer this question with almost no math at all; paying attention to the information that you're given - along with a little logic - can get you the correct answer rather quickly.
We know that Nuria was timed at 5 minutes 44 seconds, but the stop watch was NOT started until almost HALF OF A MINUTE had gone by. Thus, Nuria's actual time is greater than 5 minutes 44 second - almost HALF A MINUTE greater. There's only one answer that makes sense...
Final Answer: E
GMAT assassins aren't born, they're made,
Rich
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11/25 minutes is 11/25 x 60 = 11/5 x 12 = 26.4 secondsswerve 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
Thus, her actual time was 5 minutes 44 seconds + 26.4 seconds = 5 minutes 70.4 seconds = 6 minutes 10.4 seconds
Answer: E
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