If she started with $40 and ended up with $10, that means she must've used $30. Since the popcorn bags were all identical and she bought 12, you can divide 30 by 12 which gives you 2.5.
The answer is $2.50.
The is will be -<span>11b3</span><span> - 16b</span>2<span> + </span>4b<span> + </span><span>3</span>
All we have to do is divide the distance of the old sidewalk by 3.14:
65 / 3.14 ≈ 20.7006
That means that, rounded to the nearest meter, the new sidewalk is:
21 meters long!
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