Quantitative Aptitude - Arithmetic Ability Questions

The average revenues of 13 consecutive years of a company is Rs 70 lakhs. If the average of first 7 years is Rs 65 lakhs and that of last 7 years is Rs 77 lakhs, find the revenue for the 7th year.

If sin(A/2) = x, then the value of x is

What is the value of xy if x - y = 3 and x2+y2=15?

If the equation 4x + 3y + 5 = 0 and 6x - ky - 7 = 0 have no solution, then the value of k is

Reflection of the point (2,­7) in the y­axis is

Rahul’s salary is 40% of Mohit’s salary. If Rahul’s salary is increased by 60% and Mohit’s salary is decreased by 20%, then Rahul’s salary will be how much percentage of Mohit’s salary?

A boat is sailing towards a lighthouse of height 20√3 m at a certain speed. The angle of elevation of the top of the lighthouse changes from 30° to 60° in 10 seconds. What is the time taken (in seconds) by the boat to reach the lighthouse from its initial position?

A shopkeeper increases the price of an object by 40% and then sells it at 25% discount on the marked price. If the selling price of such an object be Rs. 2100, its cost price for the shopkeeper was ?