Nancy earns $28 for working 4 hours. How many hours does she have to work to earn $70?
Nancy earns $28/4 = $
<gadget id="calculator">28/4</gadget>
<output>7</output>
7 per hour.
Therefore, she has to work $70/$7 = 
<gadget id="calculator">70/7</gadget>
<output>10</output>
10 hours to earn $70.

<result>10</result>