The 30% off sale of a football is 42 yuan, how much is the original price.
一个足球七折销售是42元，原价是多少元．
<gadget id="calculator">70 / 100</gadget>
<output>7/10 = around 0.7</output>

<gadget id="calculator">42 / (7/10)</gadget>
<output>60</output>

<result>60</result>