Question 420260
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Hi
Arithmetic Series
{{{a[n]=a[1]+(n-1)*d}}}
{{{a[2]=a[1]+(2-1)*d = 1}}}  | {{{a[1]= 1 - d}}}
{{{a[6]=a[1]+(6-1)*d = 27}}}
  (1-d) + 5d = 27
          4d = 26
           d = 26/4 = 13/2   {{{a[1]= -11/2 }}}
CHECKING our Answer***
{{{a[2]= -11/2 + 13/2 = 1}}}