Frankie and Carla played 30 games of ping pong against each other.  Frankie won half as many games as did Carla.  How many games did Carla win?
Let x be the number of games that Frankie won.
Then the number of games Carla won would be 2*x.
And the sum of all the games would be x+2*x=30 games.
Thus, the expression simplifies to 3*x=30.
And the value of x=
<gadget id="calculator">10</gadget>
<output>10</output>
10 games.
Therefore, the number of Carla's wins would be 2x=20 games.

<result>20</result>