There is a rope with a length of 20m. Mark every 4dm from one end, and mark every 5dm. Then cut the rope at the marked place. How many pieces are the rope cut into?
有一根绳子长20m，从一端开始每隔4dm作一个记号，每隔5dm也作一个记号，然后将绳子在标有记号的地方剪断，绳子共被剪成多少段．
<gadget id="calculator">10 / 4</gadget>
<output>5/2 = around 2.5</output>

<gadget id="calculator">20 * (5/2)</gadget>
<output>50</output>

<gadget id="calculator">50 - 1</gadget>
<output>49</output>

<gadget id="calculator">10 / 5</gadget>
<output>2</output>

<gadget id="calculator">20 * 2</gadget>
<output>40</output>

<gadget id="calculator">10 / 20</gadget>
<output>1/2 = around 0.5</output>

<gadget id="calculator">20 * (1/2)</gadget>
<output>10</output>

<gadget id="calculator">10 - 1</gadget>
<output>9</output>

<gadget id="calculator">40 - 1 - 9</gadget>
<output>30</output>

<gadget id="calculator">49 + 30 + 1</gadget>
<output>80</output>

<result>80</result>