Gretchen read that you should spend 10 minutes walking for every 90 minutes you spend sitting. If Gretchen spends 6 hours working at her desk, how long will she spend walking?
First find the total number of minutes Gretchen spends sitting at her desk: 6 hours * 60 minutes/hour = 
<gadget id="calculator">6*60</gadget>
<output>360</output>
360 minutes.
Then divide this amount by 90 minutes to find how many walking breaks Gretchen takes: 360 minutes / 90 minutes/break = 
<gadget id="calculator">360/90</gadget>
<output>4</output>
4 breaks.
Then multiply the number of breaks by the length of each break to find how long Gretchen spends walking: 4 breaks * 10 minutes/break = 
<gadget id="calculator">4*10</gadget>
<output>40</output>
40 minutes.

<result>40</result>