Use a red pen to mark three times on a piece of wood: the first time to divide the wood into 12 equal parts, the second time to divide the wood into 15 equal parts, and the third time to divide the wood into 20 equal parts. Saw the wood along these marks, how many sections are sawed in total.
用红笔在一根木头上做了三次记号：第一次把木头分成12等分，第二次把木头分成15等分，第三次把木头分成20等分．沿着这些记号把木头锯开，一共锯成多少段．
<gadget id="calculator">12 - 1</gadget>
<output>11</output>

<gadget id="calculator">15 - 1</gadget>
<output>14</output>

<gadget id="calculator">60 / 20</gadget>
<output>3</output>

<gadget id="calculator">3 - 1</gadget>
<output>2</output>

<gadget id="calculator">60 / 15</gadget>
<output>4</output>

<gadget id="calculator">4 - 1</gadget>
<output>3</output>

<gadget id="calculator">60 / 12</gadget>
<output>5</output>

<gadget id="calculator">5 - 1</gadget>
<output>4</output>

<gadget id="calculator">20 - 1 - 2 - 3 - 4</gadget>
<output>10</output>

<gadget id="calculator">11 + 14 + 10 + 1</gadget>
<output>36</output>

<result>36</result>