其它
In 2010 about 120 million digital still cameras were sold worldwide.  By 2018 this number had decreased by 85\%.  About how many million digital still cameras were sold in 2018? 
Overseas Competition->Knowledge Point->Word Problem Modules->Solving Problems Involving Fractions and Percentages->Knowing the Base
$120\times（1-85\textbackslash\%）=18$ 