Use 3.14 or Start Fraction 22 over 7 End Fraction for pi.
Find the area of the circle.
A circle has a diameter of 24 centimeters.
A.
1,808.64 cm2
B. 452.16 cm2
C.
75.36 cm2
1 / 10
Solution:
Radius of the circle = diameter/2 = 24/2 = 12 cm
Using the formula for area of a circle: A = pi*r^2
A = 3.14*12^2 = 452.16 cm^2
Therefore, the area of the circle is 452.16 cm^2, option B is correct.
Note: Using 22/7 instead of 3.14 would give a slightly different answer of 452.57 cm^2, but for most purposes the approximation of pi to 3.14 is accurate enough.
Use 3.14 or Start Fraction 22 over 7 End Fraction for pi.
Estimate the area of the circle to the nearest square inch.
A circle has radius 14 inches.
A. 88 in.2
B. 62 in.2
C. 616 in.2
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Solution:
Using the formula for area of a circle: A = pi*r^2
A = 3.14 * 14^2 = 615.44 in^2
Rounded to the nearest square inch, the estimated area of the circle is 615 in^2, option C is correct.
Use 3.14 or Start Fraction 22 over 7 End Fraction for pi.
What is the area of the circle? Round your answer to the nearest square unit.
A circle has a diameter of 18 millimeters.
A. 254 mm2
B. 324 mm2
C. 1,017 cm2
3 / 10
Solution:
Radius of the circle = diameter/2 = 18/2 = 9 mm
Using the formula for area of a circle: A = pi*r^2
A = 3.14*9^2 = 254.34 mm^2
Rounded to the nearest square unit, the area of the circle is 254 mm^2, option A is correct.
Use 3.14 or Start Fraction 22 over 7 End Fraction for pi.
Estimate the area of the circle.
A circle has a radius of 70 meters.
A.
2,200 m2
B. 15,400 m2
C. 107,800 m2
4 / 10
Solution:
Using the formula for area of a circle: A = pi*r^2
A = 3.14 * 70^2 = 15,386 m^2 (rounded to the nearest square meter)
Therefore, the estimated area of the circle is 15,400 m^2, option B is correct.
Find the surface area of a cube with side length of 4.5 cm.
A. 81 cm2
B. 91.125 cm2
C. 121.5 cm2
Solution:
The surface area of a cube can be found by using the formula: SA = 6s^2, where s is the length of a side.
SA = 6 * 4.5^2 = 6 * 20.25 = 121.5 cm^2
Therefore, the surface area of the cube is 121.5 cm^2, option C is correct.
What is the surface area of the rectangular prism?
A rectangular prism has length of 1.5 millimeters, width of 1.5 millimeters, and height of 8 millimeters.
A. 52.5 mm2
B. 18 cm2
C. 28.5 cm2
6 / 10
5 of 10 Answered