Answer:
The area of the shaded region is 21.99 cm²
Step-by-step explanation:
The shaded region is the part between the two circles
The area of the shaded part is the difference between the areas of the two circles
∵ A circle with a radius of 3 cm sits inside a circle with a radius
of 4 cm
∴ The radius of the small circle = 3 cm
∴ The radius of the big circle = 5 cm
The formula of the area of a circle is A = πr²
∴ The area of the small circle = π(3)²
∴ The area of the small circle = 9π cm²
∴ The area of the big circle = π(4)²
∴ The area of the big circle = 16π cm²
The area of the shaded region = area big circle - area small circle
∴ The area of the shaded region = 16π - 9π
∴ The area of the shaded region = 7π = 21.99114858
- Round it to the nearest hundredth
∴ The area of the shaded region = 21.99 cm²
The area of the shaded region is 21.99 cm²
Find area of both circle (pi x radius^2):
4cm: 50.27
3cm: 28.27
50.27 - 22.27 = 22
22cm^2 is your answer.
Note how this is NOT 21.99 like the other answer. This is because I used exact values, where the other person used pi. Either works.
