Ext 6-8 Sampler

25 Grade6PartBLessonPlans: FindingaPercentUsingaProportion Lesson29, 6ETeacherGuide 83 Objective51: To compare2numbers as apercent. Materials: Base tenblocks,Centimeter Squares (cut from Master 3) ComparingTwoNumbers as aPercent Eachpair of students or small groupwill needbase tenblocks and centimeter squares cut from centimeter graphpaper. Writeon theboard: Elevenof 32players on the football team are seniors. What percent of the team are seniors?Roundyour answer to thenearestwholepercent. Ask students to read theproblem, find thequestion andneeded facts. Whatdifferent strategies canyouuse to solvepercentproblems? (Different strategieswill be suggested; have studentsdraw apictureof theproblem showing thepart-whole relationships.) Writeon theboard: What arewe looking for in thispercentproblem? (the ratepercent) We canuse thepicture to setupa proportion. Writeon theboard: Howdowe solve this equation for n ?Whatmustwe do toboth sidesof theequation to result in n by itself? (divideboth sides by32) Ifweare rounding to thenearest percent, how fardoweneed to carry thedivision? (to the tenths place) Beforewe round to thenearestpercent, let’suse themethodofwritinganumber sentence tofind the percent rate. Writeon theboard: R% 32 11 How canwegetRby itself on the left sideof the equation? (divideboth sides by32) 1100 = 32 n 34.3% = n Divide by 32 11 32 100 n part whole 11(100) = 32( n ) = = 0% 100% $0 32 (whole) 11 (part) n % Rate% thewholeBase number = the Part R% B=P Writeon theboard: Howdo theanswers compare? (They are the same.) Build0.343withbase tenblocks and centimeter squares. To round343 thousandths to thenearesthundredth, whatnumberdowe lookatfirst? (thenumber in the hundredths place [4]) Weneed todecidewhether this numberwill roundup.Will 0.343round to34hundredths or35hundredths?Howdoyouknow? (Students should know thepattern:When thedigit to the right is 5or greater, roundup.) Weknow that about 34%of the team is seniors. Discusswhether the answermakes senseusing the drawings and estimation. Read theproblem together at the topof thepage. Refer to thefive steps as you solve theproblem, stressing the strategyof drawing apicture. Solveproblems 1 and5 together, reminding students that thepart is always on topof thewhole,which is thedenominator. Skill Builders 51-4 R% 32 = 32 R%= 11.000 32 0.343 0.343 32 11 32 11 = = 34.3% Divide by 32 83 ©MathTeachersPress, Inc.,Reproduction by anymeans is strictly prohibited. Finding aPercent Using aProportion 16 iswhat part of 20? 20 n 1600 20 n 20 1600 20 n 80 16of the 20members of the ski club are going ona ski trip.What percent of the club is goingon the ski trip? Use thepicture towriteaproportion. Find thevalueof n . 1. 45 2. 16 n 100 45 75 n ______ % ______ ______ n ______ % 3. %of 360 is 36. ______ ______ n ______ % 4. 24 iswhat%of 40? ______ ______ n ______ % 5. Six of the40 students in class are left handed.What percent of the class is left handed? proportion:_________ answer:______ 7. The lengthof aphotographwas reduced from 180millimeters to 135 millimeters. The length of thenew photo iswhat percent of the length of the original photo? proportion:_________ answer:______ 6. Jamieanswered17 out of 25questions correctly.What percentageof the questions did he answer correctly? proportion:_________ answer:______ 8. The brainof a 50-kilogram person weighs 1.5 kilograms. Thebrain is what percent of the bodyweight? proportion:_________ answer:______ Writeaproportionand solve. 20 n 16 100 16 20 n 100 Draw A Picture 80 100 80% 16 20 n 100 Writeaproportion. Solve. 6 40 n 100 We candrawapicture to understand theproblem. Use crossproducts. Divide both sides by20. Part B 52 06 60 10 15% n 100 n 100 n 100 16 64 24 40 36 360 17 25 n 100 1.5 50 n 100 135 180 n 100 68% 3% 75% 6.RP.3, 6.RP.3c Objectives for CCSS, CCSS-CA, andTEKSnoted on lessonplans in respectiveTeacherManuals. Grade6