Li Qiang started painting landscapes at 7:30 am and finished them at 11:30 am. If he painted three pictures per hour, how many pictures did he draw in the whole morning?
李强从上午7：30开始画风景画，到11：30才画完，如果他每小时画三张，整个上午他画了多少张画？
<gadget id="calculator">3 * 4</gadget>
<output>12</output>

<result>12</result>