Use a rope to measure the depth of the well. Fold the rope in three to measure. There is 2 meters outside the well. Fold the rope in four to measure. The lower end of the rope is 1 meter from the bottom of the well. How long is the rope? (use formula to solve)
用绳子测量井深，把绳子三折来量，井外余2米，把绳子四折来量，绳在下端距井底还有1米，绳长多少米？(用算式解答)
<gadget id="calculator">1 * 4</gadget>
<output>4</output>

<gadget id="calculator">2 * 3</gadget>
<output>6</output>

<gadget id="calculator">4 + 6</gadget>
<output>10</output>

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

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

<gadget id="calculator">10 + 2</gadget>
<output>12</output>

<gadget id="calculator">12 * 3</gadget>
<output>36</output>

<result>36</result>