Mathematics and Society - OS X Lion Server

"City Has A Million Rats""2,500,000 Pines in Willumlaw Forest"How are those facts useful?How do they make such estimates?Are the numbers in these headlines exact or estimates?This page gives one possible way.1) Cut out a square region 1 cm on a side.2) Without looking, drop the square on the "city" (or "forest" or "lake") below andtrace around it. One example is already drawn. Count how many "rats" (or "trees"or "fish") are inside the square (4 in the example). This gives a sample. If thesquare does not land completely inside, drop it again.line, flip a coin to see whether to count it.If a dot is right on the"', ... ~..~3) Record in the table and tind 7 more samples.4) Find the average number (arithmetic mean) forthe 8 samples. This gives the average numberfor 1 square centimetre.5) Now find the area of the entire "city" abovein square centimetres.6) Multiply your answers in exercises 4 and 5to get an estimate of the total population.7) Count the dots to see how close your estimateis. How could you improve your estimate?SampleABCDEFGHNumber inSampleIDEA FROM:Junior Biologv: PopulationsPermission to use granted by the Board of Education of the City of Hamilton, Ontario205