Answer:
exact area of ring = 7π units²
approximate area of ring = 22 units²
Step-by-step explanation:
The shaded part of the figure is a ring. The area of the ring is calculated by subtracting the area of the inner circle from the area of the outer circle.
area of ring = area of outer circle - area of inner circle
radius of outer circle = R = 4 units
radius of inner circle = r = 3 units
area of ring = πR² - πr² = π(R² - r²)
area of ring = π[(4 units)² - (3 units)²}
area of ring = π(7 units²)
area of ring = 7π units²
approximate area of ring using π = 3.141592654
approximate area of ring = 22 units²
