The diameter of a coaster is 7 centimeters. What is the total area of five coasters? Round to the nearest hundredth if necessary.

The total areas of five coasters are 192 square centimeters, if the diameter of a coaster is 7 centimeter.

Step-by-step explanation:

The given is,

                   The diameter of a coaster is 7 centimeters

Step:1

                   Formula to calculate the area of circle,

                                ........................(1)

                 Where, r - Radius of circle

                 From given,

                           Diameter, d = 7 centimeters

                   Formula for radius,

                                                     = 3.5

                                     Radius, r = 3.5 centimeters

                     Equation (1) becomes,

                                                                   (∵ )

                                                 A = 38.465 square centimeters  

Step:2

                Area of five coasters,

                                                 = No. of coasters × Area of a coaster

                                                 = (38.465 × 3.14 )

                                                 = 192.325

                                                ≅ 192 square centimeters

Result:

          The total areas of five coasters are 192 square centimeters, if the diameter of a coaster is 7 centimeter.

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