Terri is knitting a sweater with two sleeves, a collar, and a decorative rosette. The body of the sweater takes 900 stitches to complete, the collar takes a tenth of that number of stitches, and the rosette takes twice as many as the collar. The whole sweater is an 1800-stitch project. How many stitches does each sleeve take?
The collar takes 900 / 10 = 
<gadget id="calculator">900/10</gadget>
<output>90</output>
90 stitches.
The rosette takes 2 * 90 = 
<gadget id="calculator">2*90</gadget>
<output>180</output>
180 stitches.
The body, collar, and rosette together take 900 + 90 + 180 = 
<gadget id="calculator">900+90+180</gadget>
<output>1_170</output>
1170 stitches.
Thus, the sleeves take 1800 - 1170 = 
<gadget id="calculator">1800-1170</gadget>
<output>630</output>
630 stitches.
Thus, each sleeve takes 630 / 2 = 
<gadget id="calculator">630/2</gadget>
<output>315</output>
315 stitches.

<result>315</result>