Quantitative Aptitude - Arithmetic Ability Questions

If x = a cosθ+ b sinθ and y = b cosθ- a sinθ, then x2 + y2 is equal to

If the perimeter of a semi-circle is 36 cm, then find its radius (in cm).

The list price of an article is Rs. 900. It is available at two successive discounts of 20% and 10% . The selling price of the article is:

If (-1/2) * ( x - 5) + 3 = -5/2, then what is the value of x?

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

K is 5 years older to H. H is 3 years younger to R. R is 6 years older to C. C is 7 years younger to L. Who is the eldest?

ABCD is an isosceles trapezium such that AD||BC, AB = 5 cm, AD = 8 cm and BC = 14 cm. What is the area (in cm2) of trapezium?

Ramesh uses a weight of 930 gm instead of 1 kg and sells sugar on its cost price. What will be his profit percentage on selling 15 kg sugar?