Expenditures of a company (in million rupees) per item in various yearsYear | Item of expenditure| Salary | Fuel & Bonus | Int on | Taxes| | Wages | | Loans || 1998 | 288 | 98 | 3.00 | 23.4 | 83| 1999 | 342 | 112 | 3.50 | 32.5 | 108| 2000 | 324 | 108 | 3.84 | 41.6 | 74| 2001 | 336 | 123 | 3.68 | 36.4 | 88| 2002 | 420 | 142 | 3.96 | 49.4 | 98What is the avg. interest per year which the company had to pay during this period?

If the range of $\displaystyle 28, 22, 40, 20, 15, 50$ is

If the S.D. of the $\displaystyle 1^{st}$ $\displaystyle n$ natural numbers is $\displaystyle \sqrt{30}$ then the value of $\displaystyle n$ is

If the variance of $\displaystyle 5, 7, 9$ and $\displaystyle 11$ is $\displaystyle 4$, then the coefficient of variation is:

A helicopter flies from A to B at the rate of 500 km/hr. and comes back at the rate 700 km/hr. The average speed of the helicopter is

If Arithmetic Mean (A.M.) and Geometric Mean (G.M.) of two numbers are 6.50 and 6 respectively, then the two numbers are

Which of the following is not a method of dispersion?