A red rope is 8 meters long. Grandma used 2.7 meters to make Chinese knots. Mom used as much to wrap some gift boxes as grandma. How many meters of this red rope are left?
一根红绳子长8米，奶奶做中国结用去2.7米，妈妈包装一些礼物盒用去的跟奶奶同样多，这根红绳子还剩多少米？
<gadget id="calculator">2.7 * 2</gadget>
<output>5.4</output>

<gadget id="calculator">8 - 5.4</gadget>
<output>2.6</output>

<result>2.6</result>