Question

12.35

12.35 x and s are not enough. The mean x and standard deviation s mea- sure center and variability but are not a complete description of a distribu- tion. Data sets with different shapes can have the same mean and stan- dard deviation. To demonstrate this fact, use your calculator to find and s for these two small data sets. Then make a stemplot of each and commert on the shape of each distribution. Data A: 9.14 8.14 8.74 8.77 Data B: 8,58 5.76 7.71 8.84 Data A: 9.26 8.10 6.13 3.10 Data B: 8.47 704 5.25 5.56 Data A: 9.13 7.26 4.74 Data B: .91 6.89 12.50

Answer 1

Variable Mean StDev
Data A 7.774 1.814
Data B 7.501 2.031
Using Minitab:

Stem-and-Leaf Display: Data A, Data B Stern-and-leaf of Data A N = 11 Leaf Unit 0.10 4 5 4 727 (4) 8 1177 3 9 112 Stern-and-leaf of Data B N = 11 Leaf Unit 0.10 3 5 257 5 6 58 (3) 7 079 3 8 48 9 1 10 1 12 5

Conclusion : Hence Data A is skewed to left and Data B is skewed to right.

Hope this will b helpful. Thanks and God Bless You:)