\( let \frac{1}{5}$, let $b=\frac{1}{2}$, let $c=3$, and let $d=-\frac{1}{4}$. Calculate $\frac{1}{a \cdot \frac{1}{c}} + \frac{1}{b \cdot d}$. \)
I assme that a = 1/5 b =1/2 c = 3 d = -1/4
Note that 1/ [ a * 1/c) ] = 1/ (a/c) = c/a
So we have
c/a + 1/ (b*d) =
(3) / (1/5) + 1 / ( 1/2 * -1/4 ) =
(3) * (5/1) + 1 /( -1/8) =
15 - 8 =
7
+4 
