The school originally had 36 skipping ropes, of which the ratio of the number of short ropes to long ropes was 7:2. After buying another batch of short ropes, the number of short ropes accounted for 84% of the total number of skipping ropes. How many skipping ropes does the school have in total now?
学校原有跳绳36根，其中短绳根数与长绳的比是7：2，又买进一批短绳后，短绳根数占跳绳总数的84%，现在学校一共有跳绳多少根？
<gadget id="calculator">7 + 2</gadget>
<output>9</output>

<gadget id="calculator">7 / 9</gadget>
<output>7/9 = around 0.777778</output>

<gadget id="calculator">84 / 100</gadget>
<output>21/25 = around 0.84</output>

<gadget id="calculator">1 - (21/25)</gadget>
<output>4/25 = around 0.16</output>

<gadget id="calculator">(7/9) / (4/25)</gadget>
<output>175/36 = around 4.861111</output>

<gadget id="calculator">36 * (175/36)</gadget>
<output>175</output>

<result>175</result>