For a group of students, the sum of squares of differences in ranks for Maths and Physics marks are found to be 60, which is 120 times the value of rank correlation coefficient. How many students are there in the group?

The coefficient of rank correlation in a beauty contest of 10 candidates by two judges A & B was found to be 0.5. If it was later discovered that the difference in rank of one candidate was wrongly taken as 3 instead of 7. The corrected coefficient of rank correlation is?

The coefficient of correlation between x and y is 0.6. If u & v variables are defined as $\displaystyle 2u+x-3=0$ and $\displaystyle 3v+y-2=0$ then the coefficient of correlation between u & v is?

If the plotted points in a scatter diagram are evenly distributed, then the correlation is

Speed of an automobile and the distance required to stop the car after applying brakes correlation is

A relationship $\displaystyle r^2 = 1 - \frac{500}{300}$ is not possible

If the plotted points in a scatter diagram lie from upper left to lower right, then correlation is