Question

the diameter of the larger circle is 20.4 cm.the diameter of the smaller circle is 10.8 cm.what is the best approximation for the area of the shaded region?use 3.14 to approximate pi.72.3 cm²235.1 cm²289.4 cm²326.7 cm²

Explanation:

Step1: Find radii of both circles

Radius of larger circle: $r_1 = \frac{20.4}{2} = 10.2$ cm
Radius of smaller circle: $r_2 = \frac{10.8}{2} = 5.4$ cm

Step2: Calculate area of larger circle

$A_1 = \pi r_1^2 = 3.14 \times (10.2)^2 = 3.14 \times 104.04 = 326.6856$ cm²

Step3: Calculate area of smaller circle

$A_2 = \pi r_2^2 = 3.14 \times (5.4)^2 = 3.14 \times 29.16 = 91.5624$ cm²

Step4: Subtract areas for shaded region

$A_{\text{shaded}} = A_1 - A_2 = 326.6856 - 91.5624 = 235.1232$ cm²

Answer:

235.1 cm² (matches the second option: 235.1 cm²)