WarmUp Exercises Find the area of each circle

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Warm-Up Exercises Find the area of each circle. 1. Radius 17 m ANSWER 907.

Warm-Up Exercises Find the area of each circle. 1. Radius 17 m ANSWER 907. 92 m 2 2. Diameter 7. 8 in. ANSWER 47. 78 in. 2

Warm-Up Exercises Find the volume of each solid. 3. Cylinder, radius 6 ft, height

Warm-Up Exercises Find the volume of each solid. 3. Cylinder, radius 6 ft, height 10 ft ANSWER 1130. 97 ft 3 4. Cone, radius 3. 1 cm and height 11. 8 cm ANSWER 118. 75 cm 3

Warm-Up Exercises 5. Find the circumference of a circle with radius 48 m. ANSWER

Warm-Up Exercises 5. Find the circumference of a circle with radius 48 m. ANSWER 301. 59 m

Warm-Up 1 Exercises EXAMPLE Find the surface area of a sphere Find the surface

Warm-Up 1 Exercises EXAMPLE Find the surface area of a sphere Find the surface area of the sphere. SOLUTION S = 4πr 2 Formula for surface area of a sphere. = 4π(82) Substitute 8 for r. = 256π Simplify. ≈ 804. 25 Use a calculator. ANSWER The surface area of the sphere is about 804. 25 square inches.

Warm-Up 2 Exercises EXAMPLE Standardized Test Practice SOLUTION S = 4πr 2 Formula for

Warm-Up 2 Exercises EXAMPLE Standardized Test Practice SOLUTION S = 4πr 2 Formula for surface area of a sphere. 20. 25π = 4πr 2 Substitute 20. 25π for S. 5. 0625 = r 2 Divide each side by 4π. 2. 25 = r Find the positive square root.

Warm-Up 2 Exercises EXAMPLE Standardized Test Practice The diameter of the sphere is 2

Warm-Up 2 Exercises EXAMPLE Standardized Test Practice The diameter of the sphere is 2 r = 2 2. 25 = 4. 5 centimeters. ANSWER The correct answer is B.

Warm-Up Exercises GUIDED PRACTICE 1. for Examples 1 and 2 The diameter of a

Warm-Up Exercises GUIDED PRACTICE 1. for Examples 1 and 2 The diameter of a sphere is 40 feet. Find the surface area of the sphere. ANSWER The surface area of the sphere is about 5028. 56 feet 2

Warm-Up Exercises GUIDED PRACTICE 2. for Examples 1 and 2 The surface area of

Warm-Up Exercises GUIDED PRACTICE 2. for Examples 1 and 2 The surface area of a sphere is 30π square meters. Find the radius of the sphere. ANSWER 2. 71

Warm-Up 3 Exercises EXAMPLE Use the circumference of a sphere EXTREME SPORTS In a

Warm-Up 3 Exercises EXAMPLE Use the circumference of a sphere EXTREME SPORTS In a sport called sphereing, a person rolls down a hill inside an inflatable ball surrounded by another ball. The circumference of the outer ball is 12π feet. Find the surface area of the outer ball. SOLUTION The circumference of the outer sphere is 12π feet, so the radius is 12π = 6 feet. 2π

Warm-Up 3 Exercises EXAMPLE Use the circumference of a sphere Use the formula for

Warm-Up 3 Exercises EXAMPLE Use the circumference of a sphere Use the formula for the surface area of a sphere. S = 4πr 2 = 4π(62) = 144π ANSWER The surface area of the outer ball is 144π, or about 452. 39 square feet.

Warm-Up Exercises GUIDED PRACTICE 3. for Example 3 In Example 3, the circumference of

Warm-Up Exercises GUIDED PRACTICE 3. for Example 3 In Example 3, the circumference of the inner ball is 6π feet. Find the surface area of the inner ball. round your answer to two decimal places. ANSWER 113. 10 ft 2

Warm-Up 4 Exercises EXAMPLE Find the volume of a sphere The soccer ball has

Warm-Up 4 Exercises EXAMPLE Find the volume of a sphere The soccer ball has a diameter of 9 inches. Find its volume. SOLUTION The diameter of the ball is 9 inches, so the radius is 9 2 = 4. 5 inches. 4 V = 3 πr 3 4 = 3 π(4. 5)3 Formula for volume of a sphere Substitute.

Find the volume of a sphere Warm-Up 4 Exercises EXAMPLE = 121. 5π Simplify.

Find the volume of a sphere Warm-Up 4 Exercises EXAMPLE = 121. 5π Simplify. ≈ 381. 70 Use a calculator. ANSWER The volume of the soccer ball is 121. 5π, or about 381. 70 cubic inches.

Find the volume of a composite solid Warm-Up 5 Exercises EXAMPLE Find the volume

Find the volume of a composite solid Warm-Up 5 Exercises EXAMPLE Find the volume of the composite solid. SOLUTION 1 4 3 = πr 2 h – ( πr ) 2 3 = π(2)2(2) – 2 π(2)3 3 2 = 8π – (8π) 3 Formulas for volume Substitute. Multiply.

Find the volume of a composite solid Warm-Up 5 Exercises EXAMPLE = 24 π

Find the volume of a composite solid Warm-Up 5 Exercises EXAMPLE = 24 π – 16 π 3 3 = 8 π 3 Rewrite fractions using least common denominator. Simplify. ANSWER The volume of the solid is 8 π, or about 8. 38 cubic 3 inches.

Warm-Up Exercises GUIDED PRACTICE 4. for Examples 4 and 5 The radius of a

Warm-Up Exercises GUIDED PRACTICE 4. for Examples 4 and 5 The radius of a sphere is 5 yards. Find the volume of the sphere. Round your answer to two decimal places. ANSWER The volume of the sphere is 523. 81 yd 2

Warm-Up Exercises GUIDED PRACTICE 5. for Examples 4 and 5 A solid consists of

Warm-Up Exercises GUIDED PRACTICE 5. for Examples 4 and 5 A solid consists of a hemisphere of radius 1 meter on top of a cone with the same radius and height 5 meters. Find the volume of the solid. Round your answer to two decimal places. ANSWER The volume of the solid is 7. 33 m 2

Warm-Up Exercises Daily Homework Quiz Find the surface area and volume of each sphere.

Warm-Up Exercises Daily Homework Quiz Find the surface area and volume of each sphere. 1. r = 6 ft ANSWER 452. 39 ft 2; 904. 78 ft 3

Warm-Up Exercises Daily Homework Quiz 2. d = 12. 4 m ANSWER 483. 05

Warm-Up Exercises Daily Homework Quiz 2. d = 12. 4 m ANSWER 483. 05 m 2; 998. 31 m 3

Warm-Up Exercises Daily Homework Quiz 3. A great circle of sphere has circumference 16

Warm-Up Exercises Daily Homework Quiz 3. A great circle of sphere has circumference 16 л in. . Find the volume of the sphere. ANSWER 2144. 66 in. 3

Warm-Up Exercises Daily Homework Quiz 4. Find the radius of a sphere with volume

Warm-Up Exercises Daily Homework Quiz 4. Find the radius of a sphere with volume 4445. 18 ft 3. ANSWER 10. 2 ft 5. Find the surface area and volume of the solid. ANSWER 251. 33 m 2; 335. 10 m 3