Question 474140
<pre>
 P -> Q Therefore ~Q -> ~P

P  Q  (P -> Q)  ~Q  ~P  (~Q->~P) 
T  T     T       F   F      T
T  F     F       T   F      F
F  T     T       F   T      T
F  F     T       T   T      T

They have the same truth table TFTT



Edwin</pre>