SOLUTION: When Cammie finished making a friendship bracelet, it was 7.9 inches long. What was the diameter of the bracelet? What formula would or should I use for this? Do not understand.

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Question 261768: When Cammie finished making a friendship bracelet, it was 7.9 inches long. What was the diameter of the bracelet?
What formula would or should I use for this?
Do not understand.
Found 3 solutions by unlockmath, jim_thompson5910, CharlesG2:
Answer by unlockmath(1688) About Me  (Show Source):
You can put this solution on YOUR website!
Hello,
The formula that's needed is c=pi times diameter. C stands for circumference which would be the length of the bracelet. So we can plug in the numbers to the formula as follows:
C=pi*d
7.9=3.14d Divide both sides by 3.14 to give us:
d(diameter)=2.52 inches
Make sense?
RJ
Check out a new book I wrote at:
www.math-unlock.com

Answer by jim_thompson5910(35256) About Me  (Show Source):
You can put this solution on YOUR website!
I'm assuming that the bracelet forms a circle. If you were to cut the bracelet at one point and lay it out as long as you can (without breaking it further), then the bracelet would be 7.9 inches long. Since the circumference is simply the distance out the circle, this means that the circumference is 7.9 inches. You can use the circumference formula C=pi%2Ad where pi=3.14 (approximately) and 'd' is the diameter. So just plug in C=7.9 and pi=3.14 to get 7.9=3.14d. Now just solve for 'd' in the equation 7.9=3.14d to find the diameter.

Answer by CharlesG2(834) About Me  (Show Source):
You can put this solution on YOUR website!
When Cammie finished making a friendship bracelet, it was 7.9 inches long. What was the diameter of the bracelet?
What formula would or should I use for this?
Do not understand.
Well if the bracelet approximates a circle then we can call the 7.9 inches the circumference.
The circumference of a circle is the length around the circle.
C circumference = 2 * pi * r = pi * d, where r is the radius (distance from center to edge of circle) and d is the diameter (width of the circle which is 2*r).
C = 7.9 = pi * d (now solve for d and round to nearest tenth of an inch or hundredth of an inch)
7.9/pi = d
2.51 or 2.5 inches is approximately the diameter of the bracelet