Becca, Smendrick, and PJ have collections of Magic Cards.  There is a total of 341 cards.  Becca has 12 more than Smendrick, and Smendrick has 3 times the amount of cards that PJ has.  How many cards does Becca have?
Let x represent the number of cards PJ has.
Smendrick:3x.
Becca:3x+12.
Total:x+3x+3x+12=341
7x+12=341
7x=329
x=
<gadget id="calculator">47</gadget>
<output>47</output>
47 cards.
Becca:3(47)+12=153 cards.

<result>153</result>