# Thread: Stats Quizz !! help me !!

1. ## Stats Quizz !! help me !!

This is my tutorial question but i do not understand the meaning of question B and C..Please help me..

Suppose the funnel experiment was conducted 17 times with the following results(in sec.):
5.3, 6.2, 4.8, 6.4, 5.2, 5, 6.7, 4.2, 4.3, 6.8, 4.4, 4.8, 7.1, 5.6, 6.6, 5, 4.3

a.) What proportion of outcomes are less than or equal to 5.0 seconds?

b.) What proportion of outcomes are within one standard deviation of the
mean?

c.) What proportion of outcomes are within two standard deviations of the mean?
Thank you

2. Originally Posted by Alen Won
This is my tutorial question but i do not understand the meaning of question B and C..Please help me..

Suppose the funnel experiment was conducted 17 times with the following results(in sec.):
5.3, 6.2, 4.8, 6.4, 5.2, 5, 6.7, 4.2, 4.3, 6.8, 4.4, 4.8, 7.1, 5.6, 6.6, 5, 4.3

a.) What proportion of outcomes are less than or equal to 5.0 seconds?

Mr F says: Where are you stuck here? How many values are there? How many are less than or equal to 5 seconds? Do you know how to find a proportion?

b.) What proportion of outcomes are within one standard deviation of the
mean?

c.) What proportion of outcomes are within two standard deviations of the mean?

Thank you
b.) and c.): Have you calculated the mean and standard deviation of the data? If so, what values do you get?

3. ## Yes..I got the answer for question..A

I got 0.47 for question A..

Mean is 5.453
Standard deviation is 0.986

And I do not under stand one standard deviation..and two standard deviation ..

4. Originally Posted by Alen Won
I got 0.47 for question A.. Mr F says: Correct.

Mean is 5.453
Standard deviation is 0.986

Mr says: Both correct.

And I do not under stand one standard deviation..and two standard deviation ..
Originally Posted by Alen Won
[snip]
b.) What proportion of outcomes are within one standard deviation of the
mean?

c.) What proportion of outcomes are within two standard deviations of the mean?
b.) $\bar{x} \pm s_x = 5.453 \pm 0.986 = 4.444, ~ 6.416$. So have to find the proportion of outcomes that lie between 4.444 and 6.416.

c.) is done in a similar way.