Plant a kind of sapling, the survival rate is 90%, in order to ensure 126 saplings survive, at least how many saplings should be planted.
栽一种树苗，成活率是90%，为了保证成活126棵，至少要栽多少棵树苗．
<gadget id="calculator">90 / 100</gadget>
<output>9/10 = around 0.9</output>

<gadget id="calculator">126 / (9/10)</gadget>
<output>140</output>

<result>140</result>