7th Pre-Algebra: Entering 8th 2017 Summer Practice Part 1 ... · Summer Practice Part 1: SUNGLASSES...

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7 th Pre-Algebra: Entering 8 th 2017 Summer Practice Part 1: SUNGLASSES Calculators okay if necessary Who doesn't like to wear sunglasses in the summer? Think about the math involved in the design, construction, and business of making and selling a simple pair of sunglasses. A company needs to think about fashion, materials, eye protection, sizing, advertising, and of course the bottom line. Think about buying sunglasses and how much they cost. Complete these problems by the pool with your coolest pair of shades. 1.) Suppose that 1/3 of the population of the city of Tulsa buys new sunglasses in June and 1/8 of those people buy a pair of black Ray-Bans. a.) What fraction of the population buys the black Ray-Bans? b.) Find the population of the city of Tulsa. Use the fractions to find how many people buy new sunglasses in June and how many buy the black Ray-Bans. Think how to sensibly express your answer; it represents numbers of people. Population of Tulsa: Number of sunglass buyers: Number of Ray-Ban buyers: 2.) Sunglasses come in different sizes, and there are different parts to measure. Choose a pair of sunglasses at your house. Measure several of the dimensions of the sunglasses in inches and fractions of an inch to the nearest fourth. (For example, 3 ¼ inches). Make your own sketch of the sunglasses with labeled dimensions or just label this sketch. (Which dimensions, you may ask. Up to you. Which dimensions make sense to measure?) Your 6 year-old cousin wants a pair just like yours, but they need to be three-fourths the size. What would those dimensions be? Make a sketch labeling the smaller dimensions.

Transcript of 7th Pre-Algebra: Entering 8th 2017 Summer Practice Part 1 ... · Summer Practice Part 1: SUNGLASSES...

7thPre-Algebra:Entering8th2017SummerPracticePart1:SUNGLASSESCalculatorsokayifnecessaryWhodoesn'tliketowearsunglassesinthesummer?Thinkaboutthemathinvolvedinthedesign,construction,andbusinessofmakingandsellingasimplepairofsunglasses.Acompanyneedstothinkaboutfashion,materials,eyeprotection,sizing,advertising,andofcoursethebottomline.Thinkaboutbuyingsunglassesandhowmuchtheycost.Completetheseproblemsbythepoolwithyourcoolestpairofshades.1.)Supposethat1/3ofthepopulationofthecityofTulsabuysnewsunglassesinJuneand1/8ofthosepeoplebuyapairofblackRay-Bans.a.)WhatfractionofthepopulationbuystheblackRay-Bans?b.)FindthepopulationofthecityofTulsa.UsethefractionstofindhowmanypeoplebuynewsunglassesinJuneandhowmanybuytheblackRay-Bans.Thinkhowtosensiblyexpressyouranswer;itrepresentsnumbersofpeople.

PopulationofTulsa:

Numberofsunglassbuyers: NumberofRay-Banbuyers:2.)Sunglassescomeindifferentsizes,andtherearedifferentpartstomeasure.Chooseapairofsunglassesatyourhouse.Measureseveralofthedimensionsofthesunglassesininchesandfractionsofaninchtothenearestfourth.(Forexample,3¼inches).Makeyourownsketchofthesunglasseswithlabeleddimensionsorjustlabelthissketch.(Whichdimensions,youmayask.Uptoyou.Whichdimensionsmakesensetomeasure?)Your6year-oldcousinwantsapairjustlikeyours,buttheyneedtobethree-fourthsthesize.Whatwouldthosedimensionsbe?Makeasketchlabelingthesmallerdimensions.

3.)Evensmallchangesindesigncanmakebigchangesintheamountofmaterialusedinmanufacturing.Adesignchangesavesacompany0.32gramsofplasticperpairofsunglasses.Howmuchplasticwouldbesavedin5yearsif25,000pairsofsunglassesweremanufacturedeachyear?Showthinking,ofcourse.4.)AstyleofsunglassesdesignedintheUSisgoingtobemanufacturedinEurope.MachinesintheUSuseinchesanddecimalfractionsofinches.MachinistsinEuropeusethemetricsystem,sothedesigndimensionsmustbechanged.Converteachmeasurementtomillimeters.Thinkbeforeyoudothisproblem.Whatconversionfactordoyouneed?Showyourthinking;no"one-number"answersintheboxes,please.Partmeasured Measurement

(ininches)Measurement(inmillimeters)

a.)Lenssize 2.5in.by2in.rectangle

b.)Temple-to-ear 7.12inches

c.)Pupil-to-pupil 2.84inches

5.)a.)Pleasewatchthisshortvideoanddescribethesituationitshows.http://threeacts.mrmeyer.com/doublesunglasses/act1/act1.movb.)Whatquestiondoyouhave?Writeyourquestionclearlyandcompletely.c.)Answeryourquestion;showyourthinking.6.)Asunglassescompanyearns64centsprofitoneach$1insales.Howmuchprofitdotheymakeon$2.5millioninsales?Showyourproportion.(Makesuretowrite2.5millioncorrectly!)

7.)Somedesignsaremoredifficulttomanufacturethanothers,whichmaymeanstherearemorerejectsfromthemanufacturingprocess.(Rejectsareproductsthatdonotpassinspectionsandcannotbesold.)Supposeacompanysetsalimitof7%rejectsonmanufacturing.Onemonththeyproduce16,000sunglasses;thereare1240rejects.Tellwhetherornottheyexceededthelimit;supportyouranswer.8.)Thistableshowsresultsofasurveyonproductpreferenceforfourdifferentstyles,with41%ofthosesurveyedchoosingnottobuyanyofthefourstylesshown.Fillinthetable. StyleA

StyleB StyleC StyleD

Percentofpeoplewhopreferthestyle

12% 8% 24% 15%

Numberpeopleoutof50,000whowouldbuythestyle

Profitonstyleperpairsold

$10 $12 $4 $8.50

Totalprofitonstylegivennumbersold.

9.)TheseOakleysunglassesareonsale!Whatistheoriginalprice?Showthinking.

10.)Acoolpairofsunglassesis35%offtheoriginalpriceof$54.95.Salestaxis8.5%.HowmuchdoIpayintotal?Showthinking. 11.)Lastyear,thesunglassesIlikedcost$25.50.Thisyear,theycost$29.00.Whatisthepercentincreasefromlastyeartothisyear?Roundtonearesttenthofapercent,please. 12.)Thisgraphicshows%markupsforsometypesofdesignerfashion.(http://www.businessinsider.com/products-high-markups-2014-7)Eyeglassframeshaveaverylargemarkup-muchhigherthanmarkupsweusedinproblemswedidinclass.Usethegraphictoanswerthesequestions.a.)Writethemarkup%foreyeglassframesasadecimal.b.)Supposeitcosts$7.50tomanufactureapairofframes.Usethe%markuptofindthesellingprice. c.)Supposethesellingpriceforapairofframesis$175.Usethepercentmarkuptofindthecosttomanufacturetheframes.Challenge:Thinkcarefullyonthisone!d.)Thesepricesdonotevenincludelenses!Doyouthinkdesignersunglassesareworthit?Tellwhyorwhynotinatleasttwocompletesentences.

13.)a.)Whatistheareaofacircularlenswitharadiusof2.5centimeters? b.)Whatlengthofwirewouldbeneededtogoaroundonelens? Showthinking,ofcourse!14.)CompanyresearchshowssalesofStyleAtoStyleBaretypicallyina2:5ratio.TheTulsastoresells2450pairsthismonth,andthestore'ssalesfollowthetypicalstyleratio.a.)Fillinthetabletoshowhowmanyofeachstylesold.Style Ratio TulsaStoreSales

A

B

TOTAL

b.)TheOKCstoreclaimstheircustomerslikeaviatorglasses(styleA)muchmorethanpeopleinthetypicalstore.Theysold1200pairsofStyleAand1600pairsofStyleB.Dothesenumberssupporttheclaim?Supportyouranswerwithratiothinking.15.)a.)Amanufacturersellssunglassestodepartmentstoresatapriceof$10each,andeachpaircosts$2.48tomanufacture.Whatistheamountofprofitforthemanufacturerperpairofsunglasses?(Note:profitisrevenueminuscost)b.)Themanufacturerspent$220,000inthedesignprocessandplanstospend$750,000inadvertising.Basedontheprofitforeachpaircalculatedinparta,howmanypairsofsunglasseswouldthecompanyhavetosellinordertorecoverthoseinitialcosts?Showthinkingplease.

16.)ThewordSUNGLASSESiswritteninarow8timeslikethis:SUNGLASSESSUNGLASSESSUNGLASSESSUNGLASSESSUNGLASSESSUNGLASSESSUNGLASSESSUNGLASSESThenthatrowofwordsisrepeated120timesaroundthegym.Worksmarter,nothardertoanswerthesequestions.Whatfractionofthelettersarevowels(insimplestform)? WhatpercentofthelettersistheletterS?17.)Thistableshowshowthethicknessofthelinesofonekindofmaterialaffectsthepercentofvisiblelightthatistransmittedbythematerial.Independentvariable:______________Dependentvariable:_______________Asthelensthicknessincreases,the%ofvisiblelight_______________Plotthesenumbersonthiscoordinategrid.YouMUSThavetitles,axislabels,andchooseanappropriatescale.Isthisalinearfunction?Howdoyouknow?___________________________________Whattransmissionpercentwouldyouexpectforathicknessof0.9mm?______1.9mm?____

Lensthickness(mm)

%visiblelighttransmitted

1.0 50%1.1 45%1.2 41%1.3 36%1.4 33%1.5 30%1.6 27%1.7 24%1.8 22%

7thPre-AlgebraEntering8th2016SummerPracticePart2:SkillsNOCalculators,Please.Showallthinkingandwork.Circleanswers,please.FractionApplications1.) Find the LCM and the GCF. Use any method.

a.) 28 and 29 b.) 120 and 84 2.) It takes 4/5 of a yard of fabric to make a play costume. How many costumes can be made from 52 yards? 3.) Heights of students at a school vary from 2 !!

!" feet to 5 !

! feet. Find the range of the

heights, expressed in feet. (no decimals). 4.) Find the area of this right triangle. All measurements are in inches. 2 !! 5 !

!"

4 !

!

5.) I used !

! of a 5 !

! pound bag of apples to make a pie.

a.) How many pounds did I use? b.) How many pounds are left?

6.) Fill in >, < or = Use number sense - no computation needed! a.) ⅓ + ⅓ ____ 2(⅓) b.) ½ of 64 _____ ¼ of 128 c.) ¼ • 8 ____ 8 ÷ 4 d.) ⅗ • ⅖ _____ ⅗ + ⅖ e.) ¾ ÷ ⅓ _____ 1 f.) 6 x 5______ 6 ÷ ⅕ Fraction Computation 7.) −5 !

!− 9 !

! 8.) !"

!" − !"

!"

9.) − !

!"÷ 32 10.) 1 !

! − 4 !

!"

11.) !!

!" • !"

!!" 12.) −3 !

! • 1 !"

!"

13.) 5÷ 2 !

! ∙ 2 !

! 14.) 6 !

! ÷ 3 !

! ∙ !

!

Algebraic Expressions and Equations 15.) Evaulate the expressions following order of operations.

a.) (9 − 15)! + 3 ÷ 3 b.) 90 − 12 ÷ 0.3 ÷ 2! 16.) The perimeter of a rectangular garden is 30 feet.

The length is 3 more than twice the width.

a.) Label the rectangle with variable expressions for its width and length.

b.) Write and then solve an equation to find the width AND length of the garden.

Solve equation below; write answers here: width = ______ ft length = ______ ft Solve these equations. Show all thinking. 17.) 5𝑥 + 3 𝑥 − 14 = 8 18.) 5𝑥 − 𝑥 − 5 + 7 = 15

19.) !!𝑥 − !

!+ !

!= 6 20.) !

!𝑥 − !

!+ !

! = 6

21.) 3𝑥 − 8 = 8𝑥 − 12 22.) −7 − 6𝑥 = −10 − 2𝑥

Linear Equations / Slope 23.) Which is steeper, the boat ramp or a road with a 12% grade? Support your answer by reasoning about slope. 24.)Make a table of values following our guidelines (three x values: pos, zero, neg). Graph the equation. 𝒚 = − 𝟏

𝟑𝒙 + 𝟒

25.)Find the slope of the line passing through each pair of points. No graph. Support your answer with the slope formula. A(-2, 3) B( -4, -1) 26.) Find the slope of each line from the graph. a.) b.) 27.) Solve for y to express in slope-intercept form; then use the slope-intercept form to graph the equation. No table of values.

4x + 2y = 6