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Unit 1 measurement. Group members: Boya Bill Frank Laura. agenda. Get into your groups !!(ELS groups in Miss.Murphy ’s class) Review Unit 1 : MEASUREMENT Have a groups competition Checking answers.
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Unit 1 measurement Group members: Boya Bill Frank Laura
agenda • Get into your groups!!(ELS groups in Miss.Murphy ’s class) • Review Unit 1: MEASUREMENT • Have a groups competition • Checking answers
Brain storm • Body is a “natural ruler” Can you gave us some examples.(for example your hands is about 18cm) • Do you have any examples around you.(for example the thickness of iPhone is 1cm)
Example 1 • Convert 3 feet into meters • If we put a 1-meter ruler next to a 1-foot ruler, • they would look like this: • If you then looked more closely, you would see that the 1-foot ruler came to exactly 0.3048 on the meter ruler:
Example 1 • So, the conversion for feet to meters is: 1 ft = 0.3048 meters • To convert feet to meters, multiply by 0.3048 • Let me show you why this works: to find what 3 feet would be in meters, we could put three 1 foot rulers next to each other like this:
Example 1 • So, you can see that 3 feet = 3 × 0.3048 meters = 0.9144 meters • So, 3 ft.= 0.9144 m
exercise • Let have a competition!! • QUESTION(on text book page 22) • 25mm to the nearest inch • 2.5m to the nearest foot • 10m to the nearest yard • 150km to the nearest mile
Surface areas • Area is the two-dimensional (2-D) size of a surface. Consider the area that your notebook is covering on the surface of your desk • Surface area (SA) of a solid is the total area of the exposed surfaces of a three-dimensional (3-D) object.
Surface Area Formulas • Right Pyramid • Atriangle = 1/2bs • Abase = b2 • SA = 2bs + b2
Surface Area Formulas • Rectangular • SA = 2(hl + lw + hw)
Volume formulas • Pyramid • Volume = (B × h)/3B is the area of the baseh is the height
Volume formulas • Cone • Volume = (pi × r2 × h)/3pi = 3.14r is the radiush is the height
Volume formulas • Sphere • Volume = (4 × pi × r3)/3 pi = 3.14r is the radius
Volume formulas • Rectangular • Volume = l × w × h l is the lengthw is the widthh is the height
Volume formulas • Cylinder • Volume = π× r2 × hpi = 3.14h is the heightr is the radius
Problem solution • Determine the surface area of the composite object at the right to the nearest square meter. A C B D
answer • 8*8+AB*AB=10*10 • AB=6m • CB=AB-2m=4m • CD*CD=4*4+5*5 • CD=6.4m • Scomposite object = 3*6.4+2*3+3*10+3*(5+8)+5*4*1/2*2+8*6*1/2*2 • =19.2+6+30+39+20+48 • =162.2 square meter
About volume • Determine the volume of the composite object at the right to the nearest cubic meter. A C B D
Answer • 8*8+AB*AB=10*10 • AB=6m • CB=AB-2m=4m • CD*CD=4*4+5*5 • CD=6.4m • V composite object = 6*8*3*1/2+4*5*3*1/2 • =72+30 • =102 cubic meter
Have a group competition