<PRE><B>Question 775450</B>
given: 

20 1/2, 23 1/3, 26 1/6, 29.

or you can write them this way:
41/2, 70/3, 157/6, 29, ..........

To find any term of an arithmetic sequence: 

{{{a[n]=a[1]+(n-1)*d}}} where {{{a[1] }}}is the first term of the sequence, {{{d }}}is the common difference, {{{n}}} is the number of the term to find.


{{{a[1]=20 1/2=41/2 }}}
{{{a[2]=23 1/3=70/3 }}}

{{{d =70/3-41/2=140/6-123/6=17/6}}}

{{{n=7}}}

{{{a[7]=123/6+(7-1)*17/6}}}
{{{a[7]=123/6+(6*17)/6}}}
{{{a[7]=123/6+102/6}}}
{{{a[7]=225/6}}}
{{{a[7]=75/2}}}
{{{a[7]=37 (1/2)}}}

here is more terms of your sequence:

41/2, 70/3, 157/6, 29, 191/6, 104/3, 75/2, 121/3, 259/6, 46, 293/6, 155/3, 109/2, 172/3, ...

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