# inter quartile range help!!!

• May 11th 2007, 03:08 PM
bobchiba
inter quartile range help!!!
Im either wrong or my textbook is wrong, the former being the most likely!

1 2 4 5 6 7 8 8 10 13 15

interquartile range...

I did got the lower quartile as the 3rd value and the upper as the 9th, ie 4 and 10...

so interquartile range = upper - lower...right?

so 10 - 4 = 6

im a right, text book says (9-6) = 3?
• May 11th 2007, 04:28 PM
alinailiescu
Quote:

Originally Posted by bobchiba
Im either wrong or my textbook is wrong, the former being the most likely!

1 2 4 5 6 7 8 8 10 13 15

interquartile range...

I did got the lower quartile as the 3rd value and the upper as the 9th, ie 4 and 10...

so interquartile range = upper - lower...right?

so 10 - 4 = 6

im a right, text book says (9-6) = 3?

You are right!
Good job:)
• May 12th 2007, 01:46 AM
CaptainBlack
Quote:

Originally Posted by bobchiba
Im either wrong or my textbook is wrong, the former being the most likely!

1 2 4 5 6 7 8 8 10 13 15

interquartile range...

I did got the lower quartile as the 3rd value and the upper as the 9th, ie 4 and 10...

so interquartile range = upper - lower...right?

so 10 - 4 = 6

im a right, text book says (9-6) = 3?

Yes, this is almost identical to the first example given here.

Also whatever plausible alternative definition of quartile you use 6 cannot be
the first quartile, so there is no way that the books result can be right.

RonL