The following data represents the percentages of family income allocated to groceries for a random

sample of 12 shoppers:

26 28 30 37 33 30 29 39 49 31 40

For these data, Calculate:

6.1 the mean (4)

6.2 the median (4)

6.3 the mode (4)

6.4 the standard deviation (4)

6.5 the lower quartile (4)

6.6 the upper quartile (4)

6.7 Quartile deviation (4)