Jawapan

2016-08-18T20:05:48+08:00
22/7 x j² = 38.5 .
22j² = 38.5 x 7
j² = 269.5/22
j = √12.25
j = 3.5 mm

diameter = 3.5 X 2
= 7mm
2016-08-20T22:24:35+08:00
R=radius / jejari
 \pi r^2=38.5
22/7(r^2)=38.5
r^2=12.25
r= 3.5 or -3.5
r is radius, r=3.5mm
diameter=3.5x2
answer=7mm