Question 1186612
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Notice that  {{{1/2}}} = {{{8/16}}}  and  {{{1/4}}} = {{{4/16}}}.


Having it, you can write other two rational numbers between  {{{1/2}}}  and  {{{1/4}}}  as  {{{5/16}}}  and  {{{7/16}}}, for example.


So the entire sequence of four numbers take a form


    {{{1/4}}} = {{{4/16}}},  {{{5/16}}},  {{{7/16}}},  {{{8/16}}} = {{{1/2}}}.


The two inserted terms are the second and the third in this sequence.
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