Question 1122250
You are asking for steps of five separate problem exercises.  You use your fraction skills regardless of variables or not.  Your examples have no variables.  


Too many individual exercises for one help request.  You pick one and say what is difficult about it.



The list of exercises:


a:
{{{12/16}}}


b:
{{{(4/6)(3/8)}}}


c:
{{{(2/13)}}} div.by. {{{(4/26)}}}


d:
{{{1/14+2/7}}}


e:
{{{1/12-1/14}}}


f:
{{{(1/2)/(3/4)}}}