Carla's sheepdog rounded up 90% of her sheep, but the remaining 10% wandered off into the hills. If there are 81 sheep in the pen, how many are out in the wilderness?
How many sheep were rounded up? ** First find the total number of sheep by dividing the number rounded up by 90%: 81 sheep / .9 = <<81/.9=90>>90 sheep
How many sheep are in the hills? ** Then multiply that number by 10% to find the number that are in the hills: 90 sheep * 10% = <<90*10*.01=9>>9 sheep
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