For given statistical data, the graphs for less than ogive and more than ogive are drawn. If the point at which the two curves intersect is P, then abscissa of point P gives the value of which one of the following measures of central tendency?

If the regression coefficient of x on y and y on x are $$ - {1 \over 2}$$ and $$ - {1 \over 8}$$, respectively then what is the correlation coefficient between x and y?

A sample of 5 observations has mean 32 and median 33. Later it is found that an observation was recorded incorrectly as 40 instead of 35. If we correct the data, then which one of the following is correct?

The correlation coefficient computed from a set of 30 observations is 0.8. Then, the percentage of variation not explained by linear regression is