Question 1185372: A circle with diameter 10 centimeters has an arc that is made from a central angle with degree measure 75. Find the arclength in centimeters. The following steps and conclusion form part of the solution: Step 1: Write the formula for arclength, s = rt. Step2: Substitute r = 10 and t = 75 into the formula, s = (10)(75). Step 3: Simply to s = 750. Therefore, the arclength is 750 centimeters. Is the suggested solution correct? Explain. *
Found 2 solutions by ikleyn, greenestamps:
Answer by ikleyn(52790)   (Show Source):
You can put this solution on YOUR website! .
A circle with diameter 10 centimeters has an arc that is made from a central angle with degree measure 75.
Find the arclength in centimeters. The following steps and conclusion form part of the solution:
Step 1: Write the formula for arclength, s = rt.
Step2: Substitute r = 10 and t = 75 into the formula, s = (10)(75).
Step 3: Simply to s = 750. Therefore, the arclength is 750 centimeters.
Is the suggested solution correct? Explain. *
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The suggested solution is WRONG.
It is true, that the formula for the arc length is s = r*t,
but the angle " t " in this formula is in RADIANS, not in degrees.
The second notice to your post is that the radius is not 10 in this case.
If the diameter is 10 centimeters (given), then the radius is 5 centimeters.
Answered, explained and completed.
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In whole, the posted text looks idiotic.
If your teacher gives you such problems, my advise to you is to change the class and the teacher as soon as you can.
Answer by greenestamps(13200)  (Show Source):
You can put this solution on YOUR website!
It should be obvious that the suggested solution is not right. It is nonsensical to say that an arc of a circle with diameter 10cm cut off by a central angle of 75 degrees has an arc length of 750cm...!
The problem with the solution is as the other tutor points out -- the formula s=rt for arc length gives the arc length when the radius is r and the angle is t RADIANS -- not t degrees.
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