Barney washes his kitchen towels once a week. He owns eighteen towels and uses two at a time that he changes to clean towels daily. He missed one week of laundry. How many days the following week will Barney not have clean towels?
Barney uses 2 clean towels every day, so he uses 2 * 7 = 
<gadget id="calculator">2*7</gadget>
<output>14</output>
14 towels a week.
He missed one week of laundry, so he would need 2 * 14 = 
<gadget id="calculator">2*14</gadget>
<output>28</output>
28 towels for 2 weeks.
He owns 18 towels, so he has 28 - 18 = 
<gadget id="calculator">28-18</gadget>
<output>10</output>
10 less than he needs.
Thus, Barney will not have clean towels on 10 / 2 = 
<gadget id="calculator">10/2</gadget>
<output>5</output>
5 days.

<result>5</result>