Quantitative Aptitude - Arithmetic Ability Questions

What is the value of the expression a3 - 5 + 2816a, when a = 2?

The marked price of a book is Rs 4200. The shopkeeper gives two successive discounts of 25% and y% to the customer. If the customer pays Rs 2898 for the book, then what is the value (in percentage) of y?

If x - y = -9 and xy = -20, then find x2 + y2 ?

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?

19 personswentto a hotel for a combineddinner party. 13 of them spent Rs 79 each on their dinner and the rest spent Rs 4 more than the average expenditure of all the 19. What was the total money spent by them?

If 2 shirts are offered free on purchase of 3 shirts priced Rs 600 each, then what will be the effective discount on each shirt?

If √(cosec2A - 1) = x, then the value of x is

The area of the circle with radius Y is W. The difference between the areas of the bigger circle (with radius Y) and that of the smaller circle (with radius X) is W'. So x/y is equal to