Build a staff dormitory. It is planned to use 240 6-meter-long water pipes. Later, the 8-meter-long water pipe was used. How many water pipes are used less than planned? (Solve using ratio method)
盖一幢职工宿舍．计划使用6米长的水管240根．后来改用8米长的水管，现在比计划少用多少根水管？(用比例方法解答)
<gadget id="calculator">6 * 240</gadget>
<output>1_440</output>

<gadget id="calculator">1_440 / 8</gadget>
<output>180</output>

<gadget id="calculator">240 - 180</gadget>
<output>60</output>

<result>60</result>