MeerkatCoordinatePlaneTask
GreetingsfromtheKalahariDesertinSouthAfrica!Inthisactivity,youwilllearnalotabouttheKalahari’smostplayfulresidents:meerkats.
a.Thefollowingorderedpairsshowtheheightofatypicalmeerkatatdifferenttimesduringthefirst20monthsoflife.Graphthecorrespondingpointsandseewhatyoucandiscoveraboutmeerkats.Onceyouhavegraphedthemall,connectthepointsintheordertheyaregiventoformalinegraph.
b.Whatdoesthepoint(0months,3inches)meanforatypicalmeerkat'sheight?
c.Howtalldoyouthinkatypicalmeerkatgets? Why?
d.Atwhatagedomeerkatsreachtheirfullheight?Howdoyouknowfromthisgraph?
e.Ifthisgraphwereaboutahumaninsteadofameerkat,atwhatagedoyouthinktheheightwouldstopgettinglarger?
Commentary
Thepurposeofthistaskisforstudentstoanswerquestionsaboutaproblemsituationbydrawingandinterpretingthemeaningofpointsthatareinthefirstquadrantofthecoordinateplane.Thistaskhelpstopavethewayforlaterworkinterpretingthemeaningofthey-interceptandratesofchangeinareal-worldcontext.
Thetaskendsbyaskingstudentstopredicthowthissamegraphmightrelatetohumans.Thoughthereisjustonequestionaskingstudentstoconnectthisgraphtohumans,therearemanyrelatedfollow-upquestionstoaskstudentsaswellsuchas,
“At0months,howtalldoyouthinkahumanwouldbe?”
“Wouldwewanttouseinchesandmonthsasourunitsinagraphofhumanheightovertime?Ifnot,whatunitswouldbebetter?”
“Whatwouldbethemaximum y-valueforthetypicalhuman?”“Whatwouldbe themaximumy-valueforthetypicalNBAplayer?”
Solutions:
a.
b.Thepoint(0inches,3months)meansthatwhenameerkatisfirstborn,itistypically3inchesinheight.
c.Thegraphshowsthatmeerkatsgrowtoabout12inchestallbecausenoneofthepointsgivenhasayvaluegreaterthan12.Itlookslikethemeerkathasstoppedgrowing.
d.Meerkatsstopgrowingatabout14monthsold.Atthatpoint,timecontinuestopass,butmeerkatsstayabout12inchestall.
e.Answersmayvary,butmoststudentswillpredictthathumansusuallystopgrowingatabout17yearsold.
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