Question: 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? Think carefully first, then make a decision:
First find the total number of sheep by dividing the number rounded up by 90%: 81 sheep / .9 = 90 sheep. Then multiply that number by 10% to find the number that are in the hills: 90 sheep * 10% = 9 sheep. So the answer is 9.