Google Spreadsheet Getting the last 5 values before the previous last 5

Question:

Hi, I am trying to get the average values in a row present at the last 5 rows before the last 5 rows, in other words in a sheet with 15 rows in a column I would like to know how to attain the average value of rows 5 to 10.

Solution:

Following is the screenshot of the sheet having data in column A:

Now I have the following formula in cell C1:
=arrayformula({A:A,row(A:A)})
to get the same values in column C and the row number in column D

Now I have the following formula in cell C1:
=query(arrayformula({A:A,row(A:A)}),"select Col1,Col2 where Col1 is not null",0)
to get the both columns having equal number of rows (that is rows having values in Column C)

Now I have the following formula in cell C1:
=query(arrayformula({A:A,row(A:A)}),"select Col1,Col2 where Col1 is not null order by Col2 desc",0)
to get the data in descending order of row number, as we want second last 5 rows...

Now I have the following formula in cell C1:
=query(arrayformula({A:A,row(A:A)}),"select Col1,Col2 where Col1 is not null order by Col2 desc offset 5",0)
to start the data from second last 5 rows, I have used "offset" in query formula.

Now I have the following formula in cell C1:
=query(arrayformula({A:A,row(A:A)}),"select Col1,Col2 where Col1 is not null order by Col2 desc limit 5 offset 5",0)
to limit the data upto only 5 rows.

Now I have the following formula in cell C1:
=query(arrayformula({A:A,row(A:A)}),"select Col1 where Col1 is not null order by Col2 desc limit 5 offset 5",0)
to get the data in only column C of second last 5 rows.

Now I have the following formula in cell C1:
=average(iferror(query(arrayformula({A:A,row(A:A)}),"select Col1 where Col1 is not null order by Col2 desc limit 5 offset 5",0)))
to finally get the average of second last 5 rows.