7th Grade Math

576 Volume and Surface Area

PAPER CUPS A cone-shaped paper cup is

filled with water. The height of the cup

is 7 centimeters and the diameter is

6 centimeters. If one cubic centimeter

is equal to one milliliter, how many

milliliters does the paper cup hold?

V = _^1

3

πr^2 h Volume of a cone

V = _^1

3

· π · 32 · 7 r = 3, h = 7

V ≈ 65.97 Simplify.

The paper cup holds about 66 milliliters.

c. PIÑATAS April is filling six identical cones for her piñata. Each

cone has a radius of 1.5 inches and a height of 9 inches. What is

the total volume of the cones? Round to the nearest tenth.

Real-World Link

The piñata originated

in Mexico hundreds

of years ago.

Traditionally, they are

made in the shape of

stars and human or

animal figures.

RR

T

Example 1 Find the volume of each cone. Round to the nearest tenth.

1.

14 m 13 m

2.

28 mm

6 mm

33 height: 8.4 feet, diameter: 3.5 feet

4. height: 120 millimeters, radius: 45 millimeters

Example 2 5. FUNNELS Austin is using the funnel shown

4 in.

5 in.

to fill a glass bottle with colored sand. If one

cup is about 14.4 cubic inches, about how

many cups of sand will fill the funnel at one

time? Round to the nearest tenth.

6. FLOWERS Madison is creating a floral centerpiece

16 in.

5 in.

by attaching artificial flowers to the foam cone

shown. What is the volume of the foam cone?

Round to the nearest tenth.

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