Hitunglah luas daerah lingkaran dengan diameter a.50 b.1,4 c.35 cm d.25 cm e.18cm

a) d = 50 → r = 25
L = π × r × r = 3,14 × 25 × 25 = 1962,5

b) d = 1,4 → r = 0,7
L = π × r × r = 22/7 × 0,7 × 0,7 = 1,54

c) d = 35 cm → r = 35/2 cm
L = π × r × r = 22/7 × 35/2 × 35/2 = 962,5 cm²

d) d = 25cm → r = 25/2 cm
L = π × r × r = 3,14 × 25/2 × 25/2 = 490,625 cm²

e) d = 18 cm → r = 9 cm
L = π × r × r = 3,14 × 9 × 9 = 254,34 cm²