Question 978613
Hi there,
20,(5/2),(5/16) ... 
Find 'r' Using 1st and 2nd numbers
5/2 / 20 = 5/40 = 1/8
An = 20* (1/8)^n-1
A(8) = 20*(1/8)^7
A^8 = 5/524288
Hope this helps:-)