Question

Calculati aria discului cu diametrul de 8 cm; 1 intreg si 2/5 cm; 10/п cm.

Answer 1

A disc = π • r ²

d = 2 r → r = d/2

d=8cm → r=8/2=4cm

• A= π •4 ² = 16 π cm

d=1 2/5 = 7/5 cm → r = 7/5/2 = 7/10

• A= π • (7/10)² = 49/100 π cm

d= 10/π cm → r =10/π/2 = 10/2π cm

• A= π • (10/2π)² = 100/4 π² • π = 25/π cm