5 The inner and outer diameters of a ring are 20and 36 cm respectively

1.	5 The inner and outer diameters of a ring are 20and 36 cm respectively. Find the area of the ring.cm
Answer» A_loop = (π/4)36² – (π/4)20² We can factor out the (π/4) A_loop = (π/4)(36² – 20²) We can factor (36² – 20²) getting (36 + 20)(36 - 20) A_loop = (π/4)(36 + 20)(36 - 20) A_loop = (16 • 56)(π/4) A_loop = (896/4)π = A_loop = 703.7 cm²

5 The inner and outer diameters of a ring are 20and 36 cm respectively. Find the area of the ring.cm

Answer»

A_loop = (π/4)36² – (π/4)20²

We can factor out the (π/4)

A_loop = (π/4)(36² – 20²)

We can factor (36² – 20²) getting (36 + 20)(36 - 20)

A_loop = (π/4)(36 + 20)(36 - 20)

A_loop = (16 • 56)(π/4)

A_loop = (896/4)π =

A_loop = 703.7 cm²