7th Grade Math

Extra Practice EP33

Extra Practice

Multi-Part Lesson 11-2: Similar Solids

PART A PAGES 650–651

Use the make a model strategy to solve each problem.

1. ARCHITECTURE An architect is designing a large skyscraper for a local
   firm. The skyscraper is to be 1,200 feet tall, 500 feet long, and 400 feet
   wide. If his model has a scale of 80 feet = 1 inch, find the volume of
   the model.


2. STACKING BOXES Box A has twice the volume of Box B. Box B has
   a height of 10 centimeters and a length of 5 centimeters. Box A has a
   width of 20 centimeters, a length of 10 centimeters, and a height of
   5 centimeters. What is the width of Box B?


3. TRAVEL On Monday, Mara drove 400 miles as part of her journey to
   see her sister. She drove 60% of this distance on Tuesday. If the
   distance she drove on Tuesday represents one third of her total
   journey, how many more miles does she still need to drive?


4. PIZZA On Monday, there was a whole pizza in the refrigerator.
   On Tuesday, Enrico ate 31 of the pizza. On Wednesday, he ate ^13
   of what was left. On Thursday, he ate _^12 of what remained.
   What fraction of the pizza is left?


5. GARDENS Mr. Hawkins has a circular garden in his backyard. He
   wants to build a curved brick pathway around the entire garden.
   The garden has a radius of 18 feet. The distance from the center of
   the garden to the outside edge of the brick pathway will be 21.5 feet.
   Find the area of the brick pathway. Round to the nearest tenth.

PARTS B C PAGES 652–659

1. The surface area of a triangular prism is 18.5 square inches. What is
   the surface area of a similar solid that has been enlarged by a scale
   factor of 2.5?


2. The volume of a cylinder is 630 cubic centimeters. What is the
   volume of a similar cylinder that has been reduced by a scale factor
   of _ 3 l? Round to the nearest tenth.


3. The volume of water in the first floor touch tank at the Florida
   Aquarium in Tampa is 2,016 cubic feet. Betty is making a model
   and will use a scale of _^15. What will be the volume of water in
   her model?


4. The volume of the Great Pyramid in Egypt is approximately
   33,764 cubic meters. What is the volume, to the nearest tenth, of
   a scale model that is smaller by a scale factor of _ 121?


5. The surface area of Spaceship Earth at Epcot Center is 150,000 square
   feet. What would be the surface area of a model that is decreased by
   a scale of _ 1001?

EP2_EP36_ExtPract_M1_895130.indd EP33 1/6/10 11:46 AM