UNIT 2 Measurement Topics Covered in this Unit Include: Pythagorean Theorem, Perimeter, Area and Volume and Optimization Problems Evaluations Given this Unit (Record Your Marks Here) Mastery Test – Measurement Assignment – Down by the Bay Unit Test 24 25 26 Area and Perimeters of Circles 1. Find Area & Perimeter first then cost to paint at a rate of $0.23/cm² 2. Find Area & Perimeter first then the cost to fence at a rate of $1269/km 8.5 km 4.5 cm Perimeter Area Perimeter 3. Find Area & Perimeter first then cost to paint at a rate of $11.68/m² Area 4. Find Area & Perimeter first then the cost to fence at a rate of $1310/km 6 km 5m Perimeter Problem Area Problem Perimeter Problem Area Problem 27 Additional Work a) A circular patio of radius 8 m is to be created. Find the total cost of the patio if the patio stones cost $18.99 per m² and fencing costs $16.59 per m. b)Sand will be laid down below and a fence put around a circular pool of diameter 10 m. Find the total cost sand and fencing if the sand cost $3.99 per m² and fencing costs $17.99 per m. c) A window in the shape of a half-circle must be replaced. The glass costs $0.16 per cm² and the trim costs $1.12 per cm. Find the total cost of replacing the window. d) The backyard of a home is in the shape of a half-circle. Grass costs $1.39 per m² and a fence costs $7.12 per m. Find the total cost of preparing the yard. 26 cm 13 m 28 More Areas and Perimeters Determine the area and perimeter of each of the following shapes. 1. 8.0 cm 2. 6 cm 5 cm 6.5 cm 10 cm Area = 3. Perimeter = 6.3 m Area = Perimeter = 4. 10 m 6m 4.8 m 7m 14 m Area = Perimeter = Area = Perimeter = 29 Calculating the Area and Perimeters of Composite Shapes ex. 1 15cm 6cm 9cm 7cm ex. 2 5cm 5cm 12cm 9cm 8cm ex. 3 (the shaded area) 2.5 cm 8cm 30 Areas and Perimeters of Composite Shapes Worksheet Find the area and perimeter of each of the following shapes. 1. 2. 5.8m 7cm 8.7 m 7cm 10cm 6cm 4.5m 8m 3. . 31 4. 5. 32 EQAO Sample Question – Composite Areas Dominique is helping her uncle install paving stones on the pathway in front of her house. This is the plan for the pathway. Determine the total area of the pathway. Show your work. 33 On Frozen Pond The town planners have hired you to design a rectangular ice rink for the local park. They will provide 122 metres of fencing. Your design should enclose the greatest possible area for the skaters. Explore It is possible to build a long, narrow ice rink, as shown. 56 m 5m Area = length width Area = 5 56 Area = 280 m2 Area = 280 m2 56 m On a separate page, sketch three more ice rinks that have a larger area than this ice rink. Label the dimensions on the sketch and calculate the area. Hypothesize Based on your exploration, predict the length and the width of the largest rectangular ice rink. Model Complete the table with all possible combinations of width and length for the ice rinks. Perimeter (m) Width (m) Length (m) 122 122 122 122 122 122 122 122 122 122 122 122 122 0 5 10 61 56 Area (m2) l×w 0 280 Describe what happens to the area when the width of the ice rink increases. 34 Construct a scatter plot of Area vs. Width. Manipulate Circle the region on the scatter plot where the area of the rink is the largest. On a separate page, construct two more sketches of rinks with lengths in this region. Add these points to the scatter plot. Conclude Write a report to the town advising them of the dimensions that would be best for the new ice rink. Justify your recommendation. Include a sketch and the area of the ice rink that you are recommending. 35 Measurement Performance Task Down by the Bay The city planners would also like you to design a swimming area at a local beach. There is 100 m of rope available to enclose the swimming area. The shore will be one side of the swimming area; so only three sides of the rectangle will be roped off. It is your job to design the largest rectangular swimming area. Explore It is possible to build a long, narrow swimming area. 90 m 5m 5m Area = length width Area = 5 90 Area = 450 m2 Sketch three more swimming areas that have a larger area than this swimming area and use the same 100m of rope. Label the dimensions on the sketch and calculate the area as shown above. 1. 2. 3. 36 Hypothesize Based on your exploration, predict the dimensions of the largest rectangular swimming area. Model Complete the table with possible combinations of width and length for the swimming pools. Perimeter (m) Width (m) 100 0 Length (m) Area (m2) l × w 5 Describe what happens to the area when the width of the swimming area increases. 37 Construct a scatter plot of Area vs. Width. Area Width Manipulate Look at the scatter plot. Circle the region on the scatter plot where the area of the swimming area is the largest. Construct two more sketches of swimming areas with widths and areas in this region. Add these points to the scatter plot. 38 Conclude Write a report to the town advising them of the dimensions that would be best for the new swimming area. Justify your choice. Include a sketch and the area of the swimming 39 Optimizing Perimeter and Area Worksheet 1. A farmer’s field is to be fenced in with 800m of fencing. What is the maximum area that can be enclosed using this fencing? Draw a sketch of the field and label it with the dimensions. 2. A local community centre is building a skateboard park adjacent to one of the walls of the centre. The have 60m of fencing to enclose the area. They only need to fence in 3 sides since it is next to the wall. What is the maximum area of the skateboard park. Sketch the skateboard park and label it with the dimensions that you chose. 3. A rectangular shaped skating surface has an area of 324m2. The city wants to put a fence around it. What are the dimensions of the skating area that will use the least amount of fencing? What is the total amount of fencing required? (hint: work backwards to find dimensions that will give the area specified) 4. What will the dimensions be of the skating surface in question 4 if they only need to fence in 3 sides of the skating surface? (hint: this one is tricky … use a table like you did on the performance task) 40 Pythagorean Theorem Worksheet #1 Finding the Long Side of a Right Angled Triangle (S2 + M2 = L2) 4 cm x S = M= L= 6 cm 5.5 cm y S = M= L= 5 cm x S = M= L= 12 cm 3 cm Finding the Short Side of a Right Angled Triangle (S 2 + M2 = L2) 5m x 7m S = M= L= x 11 m S = M= L= 8m 17 m y 14 m S = M= L= Finding the Middle Side of a Right Angled Triangle (S2 + M2 = L2) 3m x 6m S = M= L= S = M= L= 18 m 8m 4m 9m x S = M= L= y 41 Pythagorean Theorem Applications 1. How wide is the ramp in the following picture? 10 m 1.2 m Width =? 2. TV’s are measured based on their “diagonal” screen distance. What size is this TV? (draw the diagonal first) 20 inches 36 inches 3. How high does the ladder in the following diagram reach up the wall? 6m h 2m 42 Pythagorean Theorem Worksheet #2 Round your answers to 1 decimal place. 1. Find the value of each variable. a) x 2 122 52 b) x 2 7 2 82 d) 92 x 2 42 e) 112 82 x 2 c) x 2 10 2 92 f) 122 x 2 102 2. Find the missing measure in each triangle (assume each triangle is a right triangle) a) b) x c) 14 x 6 5 6 x 8 9 d) 15 x 11 43 3. Devon was asked to use Pythagorean Theorem to find the missing side in the following triangle. Explain (in detail) what the problem is with this question? 6 8 x 4. Find the length of the ramp in the following diagram. 1.8m 16.4m 5. Three hills in a ski resort are shown in the diagram below. Calculate the height of each. 44 Sketch a diagram to help you answer questions 6-8. 6. A ladder leans against a wall. The foot of the ladder is 1.9m from the base of the wall and the ladder reaches 4.5m up the wall. How long is the ladder? 7. A ladder that is 7.0m long is placed against a wall so that the base of the ladder is 2.1m from the base of the wall. How far up the wall does the ladder reach? 8. As a short cut to school, Joelle cuts across the diagonal of a rectangular field. If the field is 160.0m long and 120.0m wide, how much walking does Joelle save by cutting across the field instead of walking around it? 45 Volume Worksheet 9 cm 10 cm Open Topped 8 cm 15 cm 12 cm 18 cm 20 cm V= 11cm V= 12 m 6 m 10 m 10 m V= r = 10 cm V= h = 10 cm d = 8 cm 7 cm 11 cm 9 cm 4 cm V= V= 5cm 4 cm 6 cm V= 10 cm V= 46 7 cm 8 cm Open Topped 7cm 13 cm 10 cm 17 cm V= 9cm V= 17 cm 10 m 9 m 15 m 6 m V= d = 16 cm V= h = 7 cm d = 12 cm 6cm 8 cm 12 cm 3 cm V= V= 4cm 3 cm 8 cm 5 cm V= V= 47 Relationships in Measurement Comparing the Volumes of Cylinders and Cones If you have a cylinder with a base that has a diameter of 8cm and a height of 12cm and compare that with a cone that has a base with a diameter of 8cm and a height of 12cm, which one will hold the most? vs. Volume of the Cylinder Volume of the Cone What is the relationship between the volume of the cone and the volume of the cylinder? (hint: look at the formulas for both volumes) 48 Comparing the Volumes of Rectangular Prisms and Pyramids If you have a rectangular prism with a square base with sides 7cm long and a height of 9cm and compare that with a square based pyramid with the same base and height, which of the two shapes will have the smallest volume? vs. Volume of the Rectangular Prism Volume of the Square Based Pyramid What is the relationship between the volume of the prism and the volume of the pyramid? (hint: look at the formulas for both volumes) 49 Relationships in Measurement Worksheet 1. If the volume of a square-based rectangular prism is 45cm3, then what is the volume of the square-based prism with the same base and height dimensions? Explain your answer. 2. If the volume of a cone with a base of 10cm and a height of 8cm is approximately 628cm3, what is the volume of a cylinder with the same base and height dimensions? 3. Find the volume of the cone that has the same base and height as the following cylinder. (round final answer to 1 decimal place) 11 cm 9 cm 50 Volume Problems 1. Sugar cubes come in boxes containing 2 layers of cubes. Each layer forms a 12 by 6 rectangle and each cube has sides that are 1cm in length. What is the volume of the box that will hold all of the cubes? 2. Golf balls are sold in packages that hold 3 balls and are shaped like rectangular prisms. The diameter of a golf ball is 4cm. a) What is the volume of the box that holds the golf balls? b) What is the volume of each golf ball? c) How much wasted space (extra volume) is there in the box of 3 golf balls? 51 3. A tub of ice cream in the shape of a rectangular prism measures 21 cm x 15 cm x 12 cm. a) What is the volume of the ice cream container? b) If a scoop of ice cream (think spherical shapes!) has a diameter of 6cm, how many scoops of ice cream could you serve from the container? 4. A can of concentrated orange juice is shown in the image to the right. a) What is the volume of the orange juice container? b) If the manufacturer of the container wanted to change the shape so that it would hold the same amount of orange juice concentrate but only be 8.5cm tall instead of 11.6cm, what would the new dimensions be? 52 5. A can of tennis balls is shown in the diagram to the right. a) What would the volume of the canister be? b) What is the volume of each tennis ball inside of the can? c) How much wasted space would there be inside the can? d) What would the volume be of a rectangular prism shaped box that would hold the same 3 tennis balls? 53 More Applications of Volume 1. The accompanying diagram shows the side view of a pool. If the pool is 7 m wide, calculate the volume of water it can hold in cubic metres. 15 m 1m 3.5 m 6m 4m 2. A room is in the shape of a rectangular prism. Its dimensions are 7.5m, 6.0 m, and 3.0m. a) Using a ruler, draw a labeled diagram of this room. b) What volume of air (in cubic metres) can this room hold? How much would it cost to operate air cleaning unit that costs $0.67 per cubic meter each year? c) What is the area of the walls in this room? If one can of paint covers 40 m2, how many cans of paint are needed to paint this room? 54 3. A silo has a cylindrical base and a hemi-spherical roof (see diagrams below). Answer the following questions for each silo below. What is the maximum volume of grain each silo could hold? i) ii) 10 m 14 m 6m 4m 4. A spherical planet has a diameter of 6500 km. What amount of space does this planet occupy? 5. A dump truck pours out a load of gravel, creating a pile that is in the shape of a cone. If the diameter and the height of the gravel pile are 7.5 m and 4.4 m respectively, what is the volume of gravel that the dump truck delivered? 55 6. An Egyptian pyramid, which has a square base, stands 180 m from the ground at its highest point. Each side of the square base measures 220 m. a) Draw a diagram of this pyramid. b) What is the volume of this pyramid? c) Use The Pythagorean Theorem to calculate the slant height of the pyramid. 56 Measurement Review 1. For each of the following triangles, find x. a) b) x 16 x 7 cm m 15 m 12 cm 2. Find the area of the shaded region. 4 cm 9 cm 3. Consider the track below. 90m 200 m 30 m a) Find the perimeter of the track. b) Find the area inside the track. 57 4. Find the volume of the following triangular prism 7m 12 m 10 m 8m 5. Frozen ice cream treats are sold in cone-shaped containers. The containers are 12 cm high and have a 5-cm diameter. Indicate the formula you would use to determine the volume of one ice cream treat container and find the volume. What would the volume be if the container was shaped like a cylinder instead of a cone? 58 6. Mrs. Coffin wants to fence a rectangular garden in her backyard. She has 36 metres of fencing. Sketch and label the largest garden that Mrs. Coffin can enclose. Explain your reasoning. 7. If Mrs. Coffin had fenced in an area of 65m2 and used the least amount of fencing possible, what are the dimensions of the area and how much fencing did she use? 59