how to extract data from a cell in a formula in another cell

[vidhya]

hi there is problem
i have some bata in sheet1 from a1 to a240
i want the the sum of a range of these values in the cell b2 of sheet2. but
the start and end of the range i specify in cells a1 n a2 of sheet2
that is if sheet2 cells
a1=2 and a2=210
then b2 of sheet2 must contain the sum of values from a2 to a210 of sheet1.
how do i formulate this sum formula where the data of one cell is a part of
the address of another cell
kindly help
thankin in advance

 

[Tom Ogilvy]

In sheet2, b2 put in a formula like:

=sum(indirect("Sheet1!A"& a1 & ":A" & a2))