Okay I'm stuck on a word problem that involves geometry it says Kim wants to put a small fence in the shape of a circle around a tree in her backyard. She wants the radius of the circle to be 3 feet, leaving room to plant flowers around the tree. How many feet of fencing does she need to buy if it is sold by the foot? (use 3.14 to approximate pie). I am not sure how to set this problem up does it go 3.14 (3)^2 not sure how to do it?
Word problems using Geometric formulas
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BigGlenntheHeavy
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\(\displaystyle C \ = \ 2\pi r\)
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Rule #1: pie is for eating. pi is form math.
Rule #2: Please define things carefully. Never just wrote down a variable without defining it.
Rule #3: Write down stuff you know. In this case, the formula for the circumference of a circle, given its radius, is important.
1) We know the formula for the circumference of a circle is 2*pi*r, given the radius, r.
2) Since we know the radius is 3 ft, we can calculate the circumference, 2*pi*3 ft = 6*pi ft = 18.84 ft using pi = 3.14
3) We really need only 18.84 feet, but the evil lawn and garden shop will not cut it for us. We'll need to buy 19 ft.
Rule #4: Let the notation and the discussion help you. It won't all fit in your head. Think it through. Talk yourself through it.
Rule #2: Please define things carefully. Never just wrote down a variable without defining it.
Rule #3: Write down stuff you know. In this case, the formula for the circumference of a circle, given its radius, is important.
1) We know the formula for the circumference of a circle is 2*pi*r, given the radius, r.
2) Since we know the radius is 3 ft, we can calculate the circumference, 2*pi*3 ft = 6*pi ft = 18.84 ft using pi = 3.14
3) We really need only 18.84 feet, but the evil lawn and garden shop will not cut it for us. We'll need to buy 19 ft.
Rule #4: Let the notation and the discussion help you. It won't all fit in your head. Think it through. Talk yourself through it.