A Math Journey Around the WONDERS THE WORLD OF Hilary Koll Steve Mills Crabtree Publishing Company www crabtreebooks com
MISSION 1 THE PYRAMIDS OF EGYPT Your first mission takes you to Egypt Three giant stone pyramids were built there more than 3,000 years ago as burial tombs for Egyptian kings They still tower above the desert sands Your task is to figure out their sizes LEARN IT ABOUT NETS PYRAMIDS AND SURFACE AREAS A pyramid is a 3-D shape with a base and triangular faces A square-based pyramid has a square base and four triangular faces The top point of the pyramid is called its apex 04 apex face base A net is a flat pattern that is folded to make a 3-D shape The net of a square-based pyramid has four triangles the faces and a square the base joined together They can be joined in different ways One example is shown at right You can find the area of a rectangle by multiplying its length by its width So to find the area of a square multiply the length by itself To find the area of a triangle multiply the length of the base shown as b by the perpendicular height shown as h and divide the answer in half This can be shown as the formula area of a triangle ½b h To find the surface area of a pyramid find the area of each part of the net and add them together r a l u c i d n e p r e p h t h g i e h length of base b
GO FIGURE You need to find out the measurements of the pyramids so that you can add the information to your travel guide The tallest pyramid is called the Great Pyramid and was built for Pharaoh Khufu the second-tallest was built for Pharaoh Khafre and the shortest was built for Pharaoh Menkaure Plan of the site Side view with original heights and angles 143 5 m 146 5 m 230 4 m 65 5 m 215 2 m Khufu 51 3 53 2 51 8 Net of shapes 179 6 m m 906.9 Khafre 105 5m Menkaure 742 2 m the square base 1 For each pyramid find the area of 2 Due to erosion the height of Khufu’s pyramid the Great Pyramid has decreased since it was built It is now 7 7 m shorter What is its current height 186 3 m 05 84 4 m 3 Using the original heights shown above how much taller was the second-tallest pyramid than the shortest pyramid 4 For each of the pyramids use the nets to find the surface area of the whole 3-D shape
