The perimeter of a rectangle is 126 decimeters, and the ratio of length to width is 4:3. What is the length of this rectangle in decimeters?
一个长方形的周长是126分米，长和宽的比是4：3，这个长方形的长是多少分米．
<gadget id="calculator">126 / 2</gadget>
<output>63</output>

<gadget id="calculator">3 + 4</gadget>
<output>7</output>

<gadget id="calculator">4 / 7</gadget>
<output>4/7 = around 0.571429</output>

<gadget id="calculator">63 * (4/7)</gadget>
<output>36</output>

<result>36</result>