Chapter 4 Question 10 Quartile Deviation

[Karen]

Hi James

I am just working through the solutions and need a little help with (e) Quartile Deviation. Can you explain Q1 = L + (n/4 -c)i/f. What does L represent? Is n the cumulative frequency,what does c represent and what does i represent?

Q3 = L + (n 3/4 – c)i/f, can you explain what these represent.

Thank you, I have found that the textbook doesn’t seem to explain the quartile deviation regarding cumulative frequency very clearly.

Your help would be much appreciated.

Thank you

Karen

 

[James Chung]

Hi Karen,

Re: Quartile deviation for continuous series

thanks for the email.

It is hard for me to explain the processes of how to calculate Quartile Deviation and its terminologies. However, I have found a video from YouTube, Ms Chhibber explains great details of the formula and calculation.

https://www.youtube.com/watch?reload=9&v=LD5_csmGKZ0

Let me know if you have any questions. thanks.

regards,

[Karen]

Hi James

I have worked through the YouTube video as suggested. I have a question with the supplied answer. For Q3 L which is the lower limit of the class the answer says 40. Why is it not 35?

Thanks for your help

Karen

 

[Karen]

Hi James

In the You tube video for Q1 and Q3, L was the lower limit and c was the preceding class. I am a little confused.

Thanks

Karen

 

 

[James Chung]

Hi Karen,

Q3 = 37.5 – it falls in to 40 to <45. therefore the Low limit is 40.

regards