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LESSON 2.2  •   Transforming Data  105

                                                                                            5.  (a) The same shape: slightly
                     students to measure the distance from the top of     9 Taller by the inch  Refer to  Exercise 5  Suppose that
                                                                           .
                                                     .

                     their heads to the ground.      pg   100    you convert the class’s heights from inches to centi-  skewed right with several


                     (a)  What shape would this distribution of distance   meters   (1 in. =  2.54cm)  .    peaks. (b) Mean: 67 +=673in.;
                     have?                             (a)  What  shape  would  the  resulting  distribution  of   median:666

                                                                                                    += 72in. (c) SD: 4.29 in.;

                      (b)   Find the mean and median of the distribution of   height have? Explain your answer.

                     distance.                          (b)   Find  the  mean  of  the  distribution  of  height  in   IQR: 7 in.   Lesson 2.2
                      (c)   Find the standard deviation and interquartile range   centimeters.     6.  (a) The same shape: fairly symmetric

                     (IQR) of the distribution of distance.             (c)   Find the standard deviation of the distribution of

                                                       height in centimeters.               with several peaks. (b) Mean:577.3–20  =
                    6.  Long jump There were 40 athletes competing in the

                     long jump at a major track meet. The meet official     10. Jump up! Refer to  Exercise 6  Suppose that the   557.3cm; median: 577–20  = 557 cm

                                                                        .
                     recorded the distance, to the nearest centimeter, of   corrected long-jump distances are converted from   (c) SD: 4.713 cm; IQR: 7 cm

                     each  athlete’s  best  jump.  Here  are  a  dotplot  and   centimeters to meters (note that   100 cm = 1m ).
                     some numerical summaries of the data.     (a)  What shape would the resulting distribution have?   7.  (a) The shape will be the same. (b) The

                                                       Explain your answer.                 mean and median will each be $1000
                                                                             5review purposes only.

                                                        (b)   Find the mean of the distribution of corrected long-
                                                       jump distance in meters.             greater. (c) The standard deviation and

                       565  570  575  580  585          (c)   Find the standard deviation of the distribution of   IQR will each be the same.
                           Long-jump distance (cm)     corrected long-jump distance in meters.           8.  (a) The shape will be the same. (b) The

                                                      11. Making more money  Refer to  Exercise 7 . Suppose each
                     n  Mean  SD  Min  Q 1  Med  Q 3  Max  teacher receives a    5%   raise instead of a $1000 raise.   mean and median will each be $500 less.
                     40 577.3  4.713  564574.5  577  581.5  586            What effect will this raise have on each of the following   (c) The standard deviation and IQR will

                                                       characteristics of the resulting distribution of salary?
                          The meet official realized that he measured      (a)  Shape       each be the same.

                     all the jumps from the back of the board instead of

                     the front. Thus, he had to subtract 20 centimeters       (b)   Median     9.  (a) The shape will be the same:

                     from each jump to get the correct measurement.       (c)   Interquartile range           slightly skewed right with several peaks.
                     (a)  What  shape  would  the  distribution  of  corrected     12. Used cars, cheaper!  Refer to  Exercise 8 . Suppose each   (b) Mean 67 2.54 170.18 cm

                                                                                                      ×
                                                                                                           =
                                                                                                  =
                     long-jump distance have?          car’s price is reduced by    10%   instead of by $500. What
                                                                                                          =
                                                                                                     ×
                                                                                                =

                      (b)   Find the mean and median of the distribution of   effect will this discount have on each of the following   (c) SD 4.29 2.54 10.90 cm
                     corrected long-jump distance.     characteristics of the resulting distribution of price?  10.  (a) The shape will be the same:


                      (c)   Find the standard deviation and  IQR of the distri-     (a)  Shape


                     bution of corrected long-jump distance.             (b)   Mean         fairly symmetric with several peaks.
                                                                                                            =
                                                                                                       ×


                    7. Teacher raises A school system employs teachers at       (c)   Standard deviation           (b) Mean: 577.30.015.773m

                                                                                                         =
                     salaries between $38,000 and $70,000. The teach-    13 Cool pool?  Coach Ferguson uses a thermometer to   (c) SD :4.713 × 0.01 0.04713m

                                                     .
                     ers’  union  and  school  board  are  negotiating  the     pg   102   measure the temperature (in degrees Fahrenheit) at 20
                     form of next year’s increase in the salary schedule.   different locations in the school swimming pool. An   11.  (a) The shape will be the same.
                           (C) 2021 BFW Publishers -- for
                     Suppose that every teacher is given a $1000 raise.   analysis of the data yields a median of    77 F°  and an   (b) The median will be 1.05 times the


                     What effect will this raise have on each of the fol-
                     lowing characteristics of the resulting distribution   interquartile range of    5F°   Recall that   ° =C  (F  .    median of the original salary distribution.
                                                                    .

                                                                              ° − 32)
                     of salary?                                              9              (c) The IQR will be 1.05 times the IQR of


                     (a)  Shape                        (a)  Find the median temperature reading in degrees

                                                       Celsius.

                      (b)   Mean and median             (b)   Calculate the interquartile range of the temperature   the original salary distribution.


                      (c)   Standard deviation and interquartile range           readings in degrees Celsius.           12.  (a) The shape will be the same as the

                    8.  Used  cars,  cheap! A  used-car  salesman  has  28     14. Measure up  Clarence measures the diameter of each   shape of the original price distribution.
                     cars  in  his  inventory,  with  prices  ranging  from   tennis ball in a bag with a standard ruler. Unfortu-  (b) The mean will be 0.90 times the mean
                     $11,500 to $25,000. For a Labor Day sale, he   nately, he uses the ruler incorrectly so that each of his
                     reduces the price of each car by $500. What effect   measurements is 0.2 inch too large. Clarence’s data   of the original price distribution. (c) The
                     will this reduction have on each of the following   had a mean of 3.2 inches and standard deviation of   standard deviation will be 0.90 times the
                     characteristics  of  the  resulting   distribution  of   0.1 inch. Recall that    1 inch =  2.54 centimeters    .
                     price?                                                                 standard deviation of the original price


                     (a)  Shape                        (a)  Find  the  mean  of  the  corrected  measurements  in   distribution.

                                                       centimeters.
                      (b)   Mean and median             (b)   Calculate the standard deviation of the corrected


                                                                                                        5
                      (c)   Standard deviation and interquartile range           measurements in centimeters.           13.  (a) Median = (7732) 25 °C

                                                                                                                =
                                                                                                            −
                                                                                                        9
                                                                                                  5
                                                                                                      =
                                                                                            (b) IQR  = (5)2.78C
                                                                                                           °
                                                                                                  9
                                                                                                                   =
                                                                                            14.  (a) Mean (3.2 –0.2)2.547.62cm
                                                                                                     =
                                                                                                              ×
        03_StarnesSPA4e_24432_ch02_088_153.indd   105                             07/09/20   1:55 PM
                                                                                            (b) SD 0.01 2.54 0.254 cm
                                                                                                     ×
                                                                                                          =
                                                                                                =
                                                                            LESSON 2.2   •  Transforming Data         105
          03_TysonTEspa4e_25177_ch02_088_153_4pp.indd   105                                                            10/11/20   7:44 PM
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