<human>:  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?
<bot>: How many stitches does the collar take? ** The collar takes 900 / 10 = <<900/10=90>>90 stitches.
How many stitches does the rosette take? ** The rosette takes 2 * 90 = <<2*90=180>>180 stitches.
How many stitches does the whole sweater take? ** The body, collar, and rosette together take 900 + 90 + 180 = <<900+90+180=1170>>1170 stitches.
How many stitches does each sleeve take? ** Thus, the sleeves take 1800 - 1170 = <<1800-1170=630>>630 stitches.
How many stitches does each sleeve take? ** Thus, each sleeve takes 630 / 2 = <<630/2=315>>315 stitches.
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