find the area of the circle with the given radius or diameter. use "3.14" for pi. round your answer to the nearest tenth.
diameter= 42.0 mm
(1 point)
A. 137.6 mm^2
B. 376.7 mm^2
C. 1,384.7 mm^2
D. 6,027.0 mm^2
To find the area of a circle, you can use the formula:
A = π * r^2
Since the diameter is given, you can find the radius by dividing the diameter by 2:
r = d/2
r = 42.0 mm / 2
r = 21.0 mm
Now you can substitute the radius into the formula and calculate the area:
A = 3.14 * (21.0 mm)^2
A = 3.14 * 441.0 mm^2
A = 1384.74 mm^2
Rounded to the nearest tenth, the area of the circle with a diameter of 42.0 mm is 1384.7 mm^2.
So the answer is C. 1,384.7 mm^2.
whats the circumference of the circle with 3.5 cm to the nearest tenth?
To find the circumference of a circle, you can use the formula:
C = 2 * π * r
Given that the radius is 3.5 cm, you can plug this value into the formula:
C = 2 * 3.14 * 3.5 cm
C = 6.28 * 3.5 cm
C = 21.98 cm
Rounded to the nearest tenth, the circumference of the circle with a radius of 3.5 cm is 22.0 cm.
So, the circumference of the circle is 22.0 cm (to the nearest tenth).