In the afternoon, Xiaoqiang measured the length of the shadow of a certain building on the mud floor to be 10 meters. Xiaoqiang immediately inserted one-seventh of a 35-centimeter stick into the mud, so that the stick stood vertically on the ground in front of the building. Xiaoqiang measured that the length of the stick's shadow was 5 centimeters. Xiaoqiang uses these data to accurately calculate the height of the building to be d meters, and find the value of d.
在下午时分，小强在泥地上量度得某大厦的影子的长度是10米．小强实时把一根长35厘米的木棍的七份之一插入泥中，使木棍垂直竖立在大厦前面的地上，小强量度得木棍的影子的长度是5厘米．小强利用这些数据准确计算得大厦的高度是d米，求d的值．
<gadget id="calculator">35 / 100</gadget>
<output>7/20 = around 0.35</output>

<gadget id="calculator">1 / 7</gadget>
<output>1/7 = around 0.142857</output>

<gadget id="calculator">(7/20) * (1/7) * 1_200</gadget>
<output>60</output>

<result>60</result>