piece of cloth with a length of 8.2 meters takes 2.8 meters to make clothes and 2.1 meters to make trousers. How much rice is left?
一块长8.2米的布，做衣服用去2.8米，做裤子用去2.1米．还剩多少米？
<gadget id="calculator">8.2 - 2.8 - 2.1</gadget>
<output>3.3</output>

<result>3.3</result>