Melissa bought 4 packs of tennis balls for $24 in total. Each pack contains 3 balls per pack. How much did it cost Melissa for each tennis ball?
There are 4 packs of tennis balls while each pack has 3 balls. 4 * 3 = 
<gadget id="calculator">4*3</gadget>
<output>12</output>
12 balls.
Melissa spent a total of $24 for a total of 12 balls. $24 / 12 = $
<gadget id="calculator">24/12</gadget>
<output>2</output>
2 per ball.

<result>2</result>