Answer
15) Radius = 3 inches
Circumference = 18.84 inches
Area = 28.26 square inches
16) Diameter = 6 cm
Circumference = 18.84 cm
Area = 28.26 cm²
17) Diameter = 5 ft
Circumference = 15.5 ft
Area = 19.625 ft²
Step-by-step explanation
The circumference of a circle is given as
Circumference = 2πr
where
π = pi = (22/7) = 3.14
r = radius of the circle
In case the diameter is given, since the diameter is twice the size of the radius,
D = 2r
Circumference = πD
The Area of a circle is given as
Area = πr²
In terms of the diameter,
Area = (πD²/4)
So, we can answer the questions now
15) Radius = 3 inches
Circumference = 2πr
= 2π (3)
= 6π
= 18.84 inches
Area = πr²
= π(3)²
= 9π
= 28.36 square inches
16) Diameter = 6 cm
Circumference = πD
= π (6)
= 6π
= 18.84 cm
Area = (πD²/4)
= [π(6)²/4]
= 9π
= 28.36 cm²
17) Diameter = 5 ft
Circumference = πD
= π (5)
= 5π
= 15.7 ft
Area = (πD²/4)
= [π(5)²/4]
= (25π/4)
= 19.625 ft²
Hope this Helps!!!