Provide an appropriate response.
-For women at Durham College, times to run the 400 meters are normally distributed. Which of the following are the most plausible values for the mean and standard deviation?
A) Mean $= 77 \mathrm { sec }$, standard deviation $= 20 \mathrm { sec }$
B) Mean $= 77 \mathrm { sec }$, standard deviation $= 16 \mathrm { sec }$
C) Mean $= 77 \mathrm { sec }$, standard deviation $= 9.1 \mathrm { sec }$
D) Mean $= 77 \mathrm { sec }$, standard deviation $= 2.1 \mathrm { sec }$

Question

Quizplus · Accepted Answer

A standard deviation of 9.1 seconds is plausible for the 400 meters run times as it indicates a reasonable spread of times around the mean of 77 seconds. Options A and B have too large standard deviations, suggesting too wide a spread, and option D's standard deviation is too small, suggesting an unrealistically tight grouping of times.

Provide an Appropriate Response =77sec= 77 \mathrm { sec }=77sec , Standard Deviation

Provide an Appropriate Response $= 77 \mathrm { sec }$ , Standard Deviation