b) Diketahui: r = 21 cm, π = 22/7
L = π r²
L = 22/7 x 21 x 21
L 22 x 3 x 21
L = 1.386 cm²
c) Diketahui: r = 30 cm, π = 3,14
L = π r²
L = 3,14 x 30 x 30
L = 3,14 x 900
b) Diketahui: r = 21 cm, π = 22/7
L = π r²
L = 22/7 x 21 x 21
L 22 x 3 x 21
L = 1.386 cm²
c) Diketahui: r = 30 cm, π = 3,14
L = π r²
L = 3,14 x 30 x 30
L = 3,14 x 900
Editor: Muhammad Khusaini
Sumber: Buku Senang Belajar Matematika Kemendikbud 2018