Question 1093240
<br>In an infinite geometric series, if the common ratio r is between -1 and +1, then the series has a finite sum, given by the formula<br>
{{{S = a/(1-r)}}}
where a is the first term and r is the common ratio.<br>
For your series, the first term is 6 and the common ratio is -1/2.  So the sum is
{{{6/(1+1/2) = 6/(3/2) = 6*(2/3) = 4}}}