The survival rate of a kind of sapling is 90% through trial planting. How many saplings should be planted at least in order to guarantee the survival of 900 trees?
一种树苗经试种成活率是90%，为了保证种活900棵，至少应栽种多少棵树苗？
<gadget id="calculator">90 / 100</gadget>
<output>9/10 = around 0.9</output>

<gadget id="calculator">900 / (9/10)</gadget>
<output>1_000</output>

<result>1_000</result>