Jawabanmu

2013-12-16T13:19:23+07:00
A)k = 2 \pi r
      = 2.(3,14)(15)
      =94,5
b)k = 2 \pi r
     = 2.(3,14)(50)
     = 314
c)k = 2 \pi r
     = 2.(3,14)(25)
     =157
d)k = 2 \pi r
      = 2.(3,14)(30)
      = 188,4
e)k = 2 \pi r
     = 2( (\frac{22}{7} )(14)
     = 88
f)k = 2 \pi r
    = 2 (\frac{22}{7} )(21)
    = 132
Jika jari'(r) habis dibagi 7 lebih baik  \pi nya =  \frac{22}{7} , jika tidak maka  \pi = 3,14