Question 759577:  Using the figure below, determine the length of arc AB in terms of pi. (Rounded to the nearest tenth). 
 Answer by malglu(63)      (Show Source): 
You can  put this solution on YOUR website! you did  not include a picture, but this may help.  we know the circumference/length of a circle is 2 pi r, but here you have only a small part /arc of a circle.  so you need to multiply the part of the cicrle you are concerned about, with 2 pi r.  for example, if you know angle that the arc makes, then you put this as a fraction of 360 (degrees) and multiply it with 2 pi r.  keep pi as a symbol, if you need to give the answer this way.   
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