According to the given question,
For a G.P.,
\[r\text{ }=\text{ }3,\text{ }l\text{ }=\text{ }486\] and \[{{S}_{n}}~=\text{ }728\]
\[1458\text{ }-\text{ }a\text{ }=\text{ }728\text{ }x\text{ }2\text{ }=\text{ }1456\]
Hence, \[a\text{ }=\text{ }2\]
A geometric progression has common ratio = 3 and last term = 486. If the sum of its terms is 728; find its first term.
A geometric progression has common ratio = 3 and last term = 486. If the sum of its terms is 728; find its first term.