![\"\"](\"http://www.mathskey.com/userfiles/image/steps_images/step1.JPG\")
The series is ![\"\"](\"/test/fckeditor/editor/plugins/fckeditor_wiris/integration/showimage.php?formula=37fdc7f4b128d103e81bc3165253c9a5.png\")
.
Observe the series:
\The initial term is ![\"\"](\"/test/fckeditor/editor/plugins/fckeditor_wiris/integration/showimage.php?formula=c3e4edb3b234317e1ff99869638e38d5.png\")
,the sequence is excatly ![\"\"](\"http://www.mathskey.com/test/fckeditor/editor/plugins/fckeditor_wiris/integration/showimage.php?formula=897cfd6ef4365621252f1283c96e1244.png\")
to the previous term.
Therefore, the common ratio is ![\"\"](\"/test/fckeditor/editor/plugins/fckeditor_wiris/integration/showimage.php?formula=62b541ead34e394e0892fc0eb2c7eb2d.png\")
.
Therefore the sum can be calculated by using the formula: ![\"\"](\"/test/fckeditor/editor/plugins/fckeditor_wiris/integration/showimage.php?formula=ebaac6c9ee0dee7d694e32ac0b3b31b5.png\")
.
![\"\"](\"/test/fckeditor/editor/plugins/fckeditor_wiris/integration/showimage.php?formula=038811af6eabaa08588d5bacc94df3f8.png\")
.
Therefore the sum is ![\"\"](\"/test/fckeditor/editor/plugins/fckeditor_wiris/integration/showimage.php?formula=c8467d6b733e50f8d7035e62220c3b80.png\")
.
The correct option is ![\"\"](\"/test/fckeditor/editor/plugins/fckeditor_wiris/integration/showimage.php?formula=abc2ded9219572af0ce7180eb598ad95.png\")
.
![\"\"](\"http://www.mathskey.com/userfiles/image/steps_images/solution.JPG\")
The correct option is .