Xiao Ming went to the supermarket and bought 9 sets of postcards, 8 pieces in each set, and spent a total of 144 yuan. How much is each postcard?
小明去超市买了9套明信片，每套8张，一共花了144元，每张明信片多少钱？
<gadget id="calculator">9 * 8</gadget>
<output>72</output>

<gadget id="calculator">144 / 72</gadget>
<output>2</output>

<result>2</result>