Diketahui keliling lingkaran 314 cm besar sudut POQ=72 dan nilai phi=3,14 Luas juring OPQ adalah.....cm

d = kel. ÷ phi
d = 314 ÷ 3.14
d = 100 cm.
r = 50 cm.

Luas OPQ = ( 72/360) . phi . r^2
= 72/360 . 3.14 . 50 × 50
= 2/10 . 3.14 . 2500
=0.2 . 314 . 25
= 50 . 314
= 15700 cm2