Quantitative Aptitude - Arithmetic Ability Questions

The marked price of an article is Rs 960 and it is sold at a discount of Rs 192. What is the discount percentage?

If a -­ b = 3 and ab =28, then a3 - b3 is

If 2x-12x = 5, then what is the value x2 + 116x2 - 2

What is the value of sin 75°+ sin 15°?

The angle of elevation of the top of a tower from a point A on the ground is 30°. On moving a distance of 20 metres towards the foot of the tower to a point B, the angle of elevation increases to 60°. The height of the tower in meters is

D and E are points on the sides AB and AC respectively of ΔABC such that DE is parallel to BC and AD:DB = 4:5, CD and BE intersect each other at F. Then the ratio of the areas of ΔDEF and ΔCBF

If Gangadhar's salary is 3/11 times of Hari's and Shambhu's is 3/4 times of Hari's, what is the ratio of Gangadhar's salary to Shambhu's?

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