An electric fan is 128 yuan, 7 electric fans can buy 2 water heaters, how much is each water heater?
一台电风扇128元，7台电风扇的钱可以买2台热水器，每台热水器多少钱？
<gadget id="calculator">7 / 2</gadget>
<output>7/2 = around 3.5</output>

<gadget id="calculator">128 * (7/2)</gadget>
<output>448</output>

<result>448</result>