Question 326186
{{{a1=12}}}
{{{a2=3}}}
{{{a2=a1*r}}}
{{{3=12*r}}}
{{{r=1/4}}}
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{{{an=a1*r^(n-1)}}}
{{{a5=12*(1/4)^(5-1)}}}
{{{a5=12*(1/4)^(4)}}}
{{{a5=12/256}}}
{{{highlight(a5=3/64)}}}