A piece of cloth has used up 17 decimeters, and there are 3 decimeters left. How long is this piece of cloth?
一块布，用去了17分米，还剩3分米，这块布长多少米？
<gadget id="calculator">17 + 3</gadget>
<output>20</output>

<gadget id="calculator">20 / 10</gadget>
<output>2</output>

<result>2</result>