7th Grade Math

Lesson 1E Volume 573

Example 1 Find the volume of each pyramid. Round to the nearest tenth if necessary.

11

8 ft

6 ft

10 ft

2.

2.9 cm

2.2 cm

1.8 cm

Example 2 Find the height of each pyramid.

3. square pyramid: volume 1,024 cm^3 , base edge 16 cm


4. triangular pyramid: volume 48 in^3 , base edge 9 in., base height 4 in.

Example 3 5. BUILDINGS The Transamerica Pyramid is the tallest skyscraper in San

Francisco. The rectangular base has a length of 175 feet and a width of

120 feet. The height is 853 feet. Find the volume of the building.

= Step-by-Step Solutions begin on page R1.

Extra Practice begins on page EP2.

Example 1 Find the volume of each pyramid. Round to the nearest tenth if necessary.

6.

25 yd

14 yd

23 yd

7.

10.6 m

6.8 m

9.1 m

8.

7 ft

6 ft

6 ft

Example 2 Find the height of each pyramid.

9. rectangular pyramid: volume 448 in^3 , base edge 12 in., base length 8 in.


10. triangular pyramid: volume 270 cm^3 , base edge 15 cm, height of base 4 cm


11. square pyramid: volume 297 ft^3 , area of the base 81 ft^2


12. hexagonal pyramid: volume 1,320 ft^3 , area of the base 120 ft^2

Example 3 1313 GLASS A glass pyramid has a height of 4 inches. Its rectangular base has

a length of 3 inches and a width of 2.5 inches. Find the volume of glass

used to create the pyramid.

14. HISTORY An ancient stone pyramid has a height of 13.6 meters. The edges
    of the square base are 16.5 meters. Find the volume of the stone pyramid.

B 15. MATH IN THE MEDIA Find an example of a pyramid in a newspaper or

magazine, or on the Internet. Determine the pyramid’s volume.

16. MEASUREMENT A rectangular pyramid has a length of 14 centimeters, a
    width of 9 centimeters, and a height of 10 centimeters. Explain the effect
    on the volume if each dimension were doubled.

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