Write the total number of possible outcomes in a throw of 3 dice in which at least one of the dice shows an even number.

Total number of outcomes when 3 dice are thrown $=6 \times 6 \times 6=216$

Number of outcomes in which there is an odd number on all the three dice $=3 \times 3 \times 3=27$

$\therefore$ Number of outcomes in which there is an even number at least on one dice $=\{$ Total possible outcomes $\}-\{$ Number of outcomes in which there is an odd number on all the three dice $\}=216-27=189$