Housing Measurement_Section 2_Beg-Numeracy Housing Measurement: Beginning Numeracy Section 2: Calculating Perimeter EL Civics 2011-13 Unit Description: This unit is divided into three sections with each section having 3 to 5 activities. This document contains teaching materials for Section 2. Section 1: Review Converting Measurements of Length Section 2: Calculating perimeter Section 3: Calculating area Section 4: Calculating perimeter and area of irregular shapes Ronald Hubbs Center EL Civics 2011-2013 1 Housing Measurement_Section 2_Beg-Numeracy Why Measure Perimeter? (S2-A1) What things in life are shaped like squares or rectangles? square = rectangle = 1. A book 2. _________________ 3. _________________ 4. _________________ 5. _________________ 6. _________________ Perimeter is the measurement around an object. When do we need to measure the perimeter of an object? (Teacher’s Note: create a PowerPoint w/ images of when this would be useful.) 1. How many baseboards we need around a floor 2. ______________________________________ 3. _______________________________________ 4. _______________________________________ 5. _______________________________________ 6. _______________________________________ 7. _______________________________________ 8. _______________________________________ Ronald Hubbs Center EL Civics 2011-2013 2 Housing Measurement_Section 2_Beg-Numeracy Measuring Around vs. Adding sides (S2-A2: Teacher’s Notes) Materials needed: Tape measure (20 ft) Measuring tapes for students Classroom objects to measure around (book, folder, table, etc.) Teacher’s Instructions: Part 1: Hands-on Concept Building: Measuring around an object for perimeter 1. Discuss that perimeter means the measurement around an object. 2. Demonstrate measuring a square or rectangular object such as a table. For a large object, use a 20 ft tape measure to ensure you can measure the full perimeter with 1 measurement. 3. Share that measurement with the class, for example “144 in”. 4. Now measure each side at a time. Use the words ‘length’ to measure the long side and ‘width’ to measure the short side. Explain these terms (length = long side, width = short side) as they will need to know them as they continue forward in this unit. Write each measurement on the board labeled with length and width. When you finish, ask the class what to do with the 4 measurements. “How do I know how much the perimeter is?”~add~. 5. Add up the measurements together, for example “48 in + 24 in + 48 in + 24 in = 144 in. 6. Ask “Why are the measurements the same?” ~measuring all the way around is the same as adding each side together. 7. Now pass out measuring tapes to each student or pair of students. Ronald Hubbs Center EL Civics 2011-2013 3 Housing Measurement_Section 2_Beg-Numeracy Measuring Around vs. Adding sides (S2-A2: Student Handout) Teacher’s Note: Since measuring tapes often only measure to 60 inches, have students measure only small items for this activity. Also, make sure they measure at least one square item, such as the box. 1. Measure the perimeter of each object to the nearest inch by measuring around the object in one measurement. 2. Now measure the perimeter of each object by measuring one side at a time and adding the measurements together. Object Ex. a table Perimeter in one measurement Perimeter measuring each side 144 in 48 + 24 + 48 + 24 = 144 1. a book ____ + ____ + ____ + ____ = ____ 2. a folder 3. a driver’s license 4. a square box 5. a TV or computer screen Which perimeter is longer for each object, the one with one measurement or the one measuring each side at a time? Ronald Hubbs Center EL Civics 2011-2013 4 Housing Measurement_Section 2_Beg-Numeracy Finding Perimeter of a Square (S2-A3: Teacher’s Notes) Materials Needed: Tape measure to measure objects with sides longer than 60’. Measuring tapes for each student or pair Teacher Instructions: 1. Look at the measurements added together for the square box, #4 on previous handout. Ask “What do you notice (see) about the measurements of a square?” ~all four sides have the same measurement~ 2. Say “So, if all the sides of a square have the same measurement, how many sides do you need to measure? ~1 side~ “How do I get the measurement for the perimeter or all the way around the square?”~multiply by 4 –or- add the 4 sides together~ 3. Draw diagrams of two or three squares on the board. Have students come up and measure one side of each square to the nearest inch. Write the measurements next to each side measured. 4. Ask “Now, how do we find the perimeter of each square if we only have the measurement for one side?~multiply by 4 OR add the measurement 4 x” 5. Demonstrate multiplying the measured side by 4 for each square AND adding the sides 4 times. 6. Say “Let’s make a formula, an easy way to remember what math to use, to show how we find the perimeter of a square. We measure 1 side, we can call that side a. We multiply the side by 4. The formula is 4a = P, where a = 1 side, the 4 in front means to multiply by 4, and the P = perimeter. 4a = P” 7. Show how the formula represents what you already did to find the perimeter for the squares on the board. 8. Demonstrate with 2 or 3 square objects step-by-step as above, highlighting the formula each time. Ronald Hubbs Center EL Civics 2011-2013 5 Housing Measurement_Section 2_Beg-Numeracy Finding Perimeter of a Square (S2-A3:Student Handout) Measure the length of one side of each square to the nearest inch. Write the measurement on the line. Use the formula to find the perimeter. 1. Length = ____________ 4a = P 4 x ______ = ___________ 2. Length = ____________ 4a = P 4 x ______ = ___________ 3. Length = ____________ 4a = P 4 x ______ = ___________ Ronald Hubbs Center EL Civics 2011-2013 6 Housing Measurement_Section 2_Beg-Numeracy Finding Perimeter of a Rectangle (S2-A4: Teacher’s Notes) Materials Needed: Tape measure to measure objects with sides longer than 60’. Measuring tapes for each student or pair Teacher Instructions: 1. Look at the measurements added together in the “Perimeter measuring each side” column from activity S2-A2. Have students look at the pattern they see from the side measurements ~a + b + a + b; the 2 measurements of the length are the same & the 2 measurements of the width are the same~ 2. Ask “Why are the 2 lengths the same? Why are the 2 widths the same” ~the 2 opposite sides (sides across from each other) are the same length~ 3. Discuss how in a rectangle the opposite sides are the same length, the lengths are equal and the widths are equal. Draw diagrams on the board to explain this. 4. “So, if the lengths are the same and the widths are the same, do I have to measure all four sides?”~no~ “How many sides do I have to measure?”~2 sides; the length and the width.~ 5. Say “If I measure only one length and one width (demonstrate this using the same table measured in S2-A2 and then add them together, do I get the perimeter?” ~no~ “Why not?” ~because there are 2 more sides, that’s only half.~ 6. Ask “What do I need to do then? I measure the length and I know the opposite side is the same. So if it is 48 in. on this side, I know it is also 48 in on that side. So, what do I do with the number 48?” ~multiply by 2 (or add together, but make sure students see that multiplying by 2 is the same as adding the 2 sides together)~ 7. Write on the board 48 x 2 length. 8. Say “I measure the width and I know the opposite side is the same. So if it is 24 in. on this side, I know it is also 24 in. on that side. So, what do I do with the number 24?” ~multiply by 2~ 9. Write on the board 24 x 2 width. 10.Say “I have 48 x 2 length and 24 x 2 width. How much is 48 x 2?” ~96 in.~ “How much is 24 x 2?” ~48 in.~ Write answers on the board. “What do I do with those 2 numbers?” ~add them together~ 11.Write 96 + 48 = ? “What is the answer?” ~144 in.~ 12.Write “2 x a (1 side) + 2 x b (the other side) = perimeter” on the board. 13.Compare this formula to what you just demonstrated to the class. 14.Shorten the formula to 2a + 2b = perimeter. Explain that the abbreviated form means the same thing. Explain that this is called a “formula” or short way to figure Ronald Hubbs Center EL Civics 2011-2013 7 Housing Measurement_Section 2_Beg-Numeracy out a math problem. This shows that you don’t have to measure each side, but just the length and width, multiply each by 2, and add them together. 15.Demonstrate with 2 or 3 more classroom objects step-by-step as above, highlighting the formula each time. You could use the items they measured in S2-A2 to show that the answer will be the same. Ronald Hubbs Center EL Civics 2011-2013 8 Housing Measurement_Section 2_Beg-Numeracy Finding Perimeter of a Rectangle (S2-A4: Student Handout) Teacher’s Note: Pass out a measuring tape to each student or pair of students. Directions: Measure the length and width of the objects to the nearest inch and write the measurements in the chart. Use the formula you practiced to find the perimeter. Formula: _________________________________ Object Ex. Table Length Width 48 in. Perimeter: 2a + 2b = Perimeter 2 x 48 + 2 x 24 in. = 96 + 48 = 144 in. 24 in. 1. your table 2. your paper 3. the whiteboard 4. the TV or computer screen 5. the map 6. the window 7. the door 8. the top of the cabinet Ronald Hubbs Center EL Civics 2011-2013 9 Housing Measurement_Section 2_Beg-Numeracy Perimeter in Feet & Inches (S2-A5: Teacher’s Notes) Materials Needed: Tape measures for measuring objects in feet and inches. (Ideally, 1 tape measure for each group of 3 or 4 students.) Teacher’s Instructions: 1. Explain that when we measure a longer length and width, we would use a tape measure. A tape measure gives us the measurement in feet and inches. 2. Measure a large square object in feet and inches. Demonstrate that all 4 sides are the same. 3. Write the measurement of one of the sides of the square on the board. If neither length nor width have extra inches, you should measure an object that does. 4. Now apply the formula (4a = P) to the measurement. Show how we multiply each unit by four. Ex. 3 ft 4 inches X4 12 ft 16 inches 5. Now explain that 16 inches is larger than a foot so we need to “convert” it to feet (and inches). “How much is 1 foot?” ~12 inches~ What do we do when we change inches to feet?” ~divide~ “So, 16 ÷ 12 = ? How many times does 12 go into 16? ” ~1~. “How many extra inches are there?” ~4 inches~ “How do you know that?” ~Multiply 12 by 1 = 12 inches. Subtract 12 inches from 16 = 4~ Ex. 1 ft 4 inches 12 x 1 = 12 12 16 Subtract 12 from 16 -12 Remainder 4 inches 4 6. Now measure the length and width of a rectangular object, such as the table. Write the length & width on the board in feet and inches. If neither length nor width have extra inches, you should measure an object that does. 7. Write: (for example) Length (side a) = 3 ft. 11 in. width (side b) = 1 ft. 11 in. 8. Apply the formula 2 x (3 ft 11 in). Review how to multiply ft. and inches. Ex. 3 ft 11 inches 1 ft 10 inches X2 12 22 6 ft 22 inches -12 10 inches 6 ft + 1 ft. 10 in. = 7 ft 10 in 9. Repeat with 2 x (1 ft. 11 in.) Then add the answers together. Ronald Hubbs Center EL Civics 2011-2013 10 Housing Measurement_Section 2_Beg-Numeracy Perimeter in Feet & Inches (S2-A5a:Student Handout) Teacher’s Note: Pass out a tape measure to each student or pair of students. Directions: Measure the length and width of the objects in feet and inches to the nearest inch and write the measurements in the chart. Use the formula you practiced to find the perimeter. Formula: _________________________________ Object Length Width Ex. Table 3 ft. 11 in. 1 ft. 11 in. 2a = 2 x 3 ft. 11 in = 3 ft 11 inches 1 ft 10 in. X2 12 22 6 ft 22 in. -12 10 in. 6 ft + 1 ft. 10 in. = 7 ft 10 in Perimeter: 2a + 2b = P 2b = 2 x 1 ft. 11 in = 1 ft 11 inches 1 ft 10 in. X2 12 22 2 ft 22 in. -12 10 in. 2 ft + 1 ft. 10 in. = 3 ft 10 in 1 ft 8 in 7 ft 10 in + 3 ft 10 in = 10 ft 20 in. 12 20 10 ft. + 1 ft. 8 in. = 11 ft. 8 in. -12 8 in. 1. Your Table Perimeter: 2a + 2b = P 2. Whiteboard Perimeter: 2a + 2b = P Ronald Hubbs Center EL Civics 2011-2013 11 Housing Measurement_Section 2_Beg-Numeracy Perimeter in Feet & Inches (S2-A5b:Student Handout) Directions: Use the measurements you took for the activity before. Now you will calculate perimeter by converting to the smallest measurement first, finding the perimeter, and then converting back to feet & inches. Formula: _________________________________ Object Ex. Table Length 3 ft. 11 in. Width 1 ft. 11 in. 2a = 2 x 3 ft. 11 in = 3 ft 11 inches X 12 36 in + 11 in. = 47 in. 2 x 47 in = 94 inches Perimeter: 2a + 2b = P 94 in + 46 in = 140 in. P = 11 ft 8 in. 1. Your Table Perimeter: 2a + 2b = P 2. Whiteboard Perimeter: 2a + 2b = P Ronald Hubbs Center EL Civics 2011-2013 12 2b = 2 x 1 ft. 11 in = 1 ft 11 inches X12 12 in. + 11 in. = 23 in. 10 in. 2 x 23 in = 46 inches 11 ft 8 in 12 140 -12 20 in. -12 8 in. Housing Measurement_Section 2_Beg-Numeracy Perimeter Activity (S2) Home Decorating Project: You bought curtains for your living room. You like the curtains but you want to make them prettier. You decide to sew a border of ribbon all around the curtains to add color. Look at the diagram of the curtains on the next page. Now follow the directions. 1. What color curtains did you buy? Note: Think about the color of your living room. What color would look nice? 2. What color ribbon do you want to add? Note: Think about the color of the curtains. What color would look good with this color? This is called an “accent” color. 3. Color the diagram with the colors you chose. Use markers, crayons, or colored pencils. If white, leave blank. 4. Now measure the windows in feet (and inches if extra inches). You can measure the windows in your living room and bring those measurements to class or you can measure the windows in your classroom to use as an example. Note: Your curtains need to be long enough to cover the top and bottom of the window frame. They need to be wide enough to cover both the left and right of the window frame. 5. Write your measurements on the diagram and worksheet. 6. Now think about how much ribbon you need to buy. Look at the diagram. Curtains are not just 1 piece of fabric. They come with 2 “panels” or pieces of fabric. The ribbon must go around each panel. 7. Calculate the perimeter of one of the shapes. Square: 4a = P Rectangle: 2a + 2b = P 8. There are 2 curtain panels. So how much ribbon (in feet and inches) do you need in total? Round your inches 9. Ribbon is sold by the yard. You need to convert your measurements to yards. First, round your inches up to the next foot. Then convert to yards. Remember: 3 feet = 1 yard Ronald Hubbs Center EL Civics 2011-2013 13 Housing Measurement_Section 2_Beg-Numeracy Curtains Diagram (S2) 1. Color the inside of the curtain panels 2. Color the ribbon border of the curtain panels. 3. Measure the window(s) and write the measurements on the diagram. Curtain Panel 1 ½ Window Length: ______________ Ronald Hubbs Center EL Civics 2011-2013 14 Curtain Panel 2 ½ Window Length: ______________ Window Height ____________________ Window Height ____________________ Window Length: _______________________ Housing Measurement_Section 2_Beg-Numeracy Perimeter Activity Worksheet (S2) 1. Curtain Fabric Color: __________________________ 2. Curtain Ribbon Color: _________________________ 3. Window Length: __________________________ 4. ½ Window Length _______________________ 5. Window Height: __________________________ 6. Calculate the perimeter of one of the curtain panels: 7. My curtain panel is a square rectangle. (Circle one) The formula I will use is: (Circle one below) Square: 4a = P -OR- Rectangle: 2a + 2b = P My Calculations: Length = ___________ Height = ___________ Perimeter = _________ ft and ______ inches 8. You will need ribbon for 2 curtain panels. Multiply the perimeter by 2: __________________ x 2 = _______________________ 1 panel Perimeter 2 panels Perimeter 9. I will need a total of _________feet ______ inches of ribbon. 10. Round the inches up to the next foot. Note: You need to make sure to have enough ribbon so rounding down is not a good idea. I will need ___________ feet of ribbon. 11. Ribbon is sold by the yard. You need to convert feet to yards: Remember: 3 feet = 1 yard ________ = ? yards Total feet 3 feet = 1 yard Divide down I will need ________ yards _______ (extra) feet of ribbon. Ronald Hubbs Center EL Civics 2011-2013 15