Ursula is working at a marketing firm. She created a 30-second long commercial. Her boss told her that this commercial is too long to air and told her to shorten the commercial by 30%. How long will this commercial be after Ursula makes the desired changes?
Ursula's boss want's the commercial to be 30/100 * 30 = 
<gadget id="calculator">30/100*30</gadget>
<output>9</output>
9 seconds shorter.
After Ursula makes the desired changes, the ad is going to be 30 - 9 = 
<gadget id="calculator">30-9</gadget>
<output>21</output>
21 seconds long.

<result>21</result>