The article "Snow Cover and Temperature Relationships in North America and Eurasia" (J. Climate and Applied Meteorology, 1983: 460–469) used statistical techniques to relate the amount of snow cover on each continent to average continental temperature. Data presented there included the following ten observations on October snow cover for Eurasia during the years 1970–1979 (in million km2):

From the given information, the ten observations data on October snow cover for the Eurasia during a year is,

6.5 12.0 14.9 10.0 10.7 7.9 21.9 12.5 14.5 9.2

For the given data, 21.9 is an outlier, so trimmed mean would be good choice for the researcher.

Remove the smallest and the largest values to compute the trimmed mean.

= (12.0 +14.9 +10.0 +10.7 + 7.9 +12.5 +14.5 + 9.2) / 8

= 91.7 / 8

= 11.4625

the answer is 5/3x+7/5y+7

the direct variation says that:

then the equation is of the form is given by:

            where k is the constant variation.

from the given table:

consider any value of x and m(x)=y

x = 2 and m(x)=y = 3

substitute these value in [1]; we have;

divide both sides by 2 we get;

⇒

check:

put x = -1 and m(x) = -1.5

substitute in the equation:

-1.5 = -1.5                   true

therefore, the function m(x) represents a direct variation

graph of this function as shown below: