Jawabanmu

2014-09-08T18:03:19+07:00
L=2\pi rt
L=2x\frac{22}{7} x r x t
528 =2x\frac{22}{7} x r x 12
528 = \frac{258}{7} xr
r = 528 : \frac{528}{7}
r = 528 x \frac{7}{528}
  = 7 cm
jadi,panjang jari-jari alas = 7 cm