Dave breaks 2 guitar strings per night when playing live.  If he performs 6 shows a week for 12 weeks, how many guitar strings will he need to replace?
He breaks 2 strings a night for 6 nights for a total of 2*6 = 
<gadget id="calculator">2*6</gadget>
<output>12</output>
12 broken strings.
He breaks 12 strings per week so over 12 weeks, he will need to replace 12*12 = 
<gadget id="calculator">12*12</gadget>
<output>144</output>
144 guitar strings.

<result>144</result>