# GATE Papers >> CSE >> 2016 >> Question No 40

Question No. 40

Consider the two cascaded 2-to-1 multiplexers as shown in the figure.

The minimal sum of products form of the output $X$ is

Solution of Question No 40 of GATE 2016 CSE Paper

MUX-1 output ⇒ $\overline P\left(0\right)+P\left(R\right)=PR$

MUX-2 output ⇒ $X=\overline Q\left(\overline R\right)+Q\left(PR\right)$

$=\overline Q\overline R+PQR$