The sales aunt told Aunt Chen that the price of milk would increase, and the price of 36 yuan a box of milk would rise to 45 yuan. Aunt Chen immediately bought 7 boxes. How much money did she save?
售货阿姨告诉陈阿姨牛奶将要涨价，36元一箱的牛奶将要涨到45元，陈阿姨立刻买了7箱，她节省了多少钱？
<gadget id="calculator">45 - 38</gadget>
<output>7</output>

<gadget id="calculator">7 * 7</gadget>
<output>49</output>

<result>49</result>