Here, we want to get the value of the expression given the value of j
To do this, we simply need to make a substitition for j by using the given value
Thus, we have this as;
[tex]\frac{18}{23}-\frac{1}{2}[/tex]We get the lowest common factor of 23 and 2 which is 46;
Then we divide 46 by each denominator after we multiply the result of the division by the numerator of each fraction
Thus, we have;
[tex]\frac{2(18)-23}{46}\text{ = }\frac{36-23}{46}\text{ = }\frac{13}{46}[/tex]