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Intro-Stat, Math 203, Candy bar Quiz 2
  1. Archaeopteryx is an extinct beast having feathers like a bird but teeth and a long bony tail like a reptile. The table below gives the lengths (in centimeters) of two bones from each of 5 fossil specimens from these beasts. Let X = length of the Femur bone and Y = length of the Humerus bone. A scatterplot of the data is also given.
X = Femur Length 38 56 59 64 74
Y = Humerus Length 41 63 70 72 84
      1. Does the scatterplot show a positive or negative association?








      2. Do you think that the correlation, r, is
        1. close to -1
        2. negative but not too close to -1
        3. about zero
        4. positive but not too close to 1
        5. close to 1










      3. Find an equation for the least squares regression line.













      4. Use your regression equation to predict the length of the humerus, if the femur is 50 cm long.