Quantitative Aptitude - Arithmetic Ability Questions

If the standard deviation of a population is 6.5, what would be the population variance?

In the following question, select the odd word pair from the given alternatives.

If sin ­-330° = x, then the value of x is

In the following question, select the missing number from the given series.
 
1912, 2012, 2133, 2277, 2446, ?

What will be the value of xy, if x2+y2 = 45 and x-y=5 ?

A boy spends Rs 20 to purchase toffees at Rs 1 each. Next day, he purchased some toffees for Rs 40 with a discount of 50 paise per toffee. What is the average price per toffee (in paise)?

Six year ago Parvez’s age was same as the present age of Manish. If the present age of Parvez is one-fourth more than that of Manish's present age, then in how many years will Parvez’s age become double of Manish’s present age?

The point P(-­4,1) divides the segment joining the points (x,0) and (0,y) in the ratio 3:2. Find x and y?