Quantitative Aptitude - Arithmetic Ability Questions

Vijay can do a work in 8 hours. Vijay and Puneet together can do the same work in 6 hours. Puneet and Sachin together can do the same work in 4 hours. Sachin alone can complete the same work in how many hours?

Each question contains Quantity I and Quantity II. Read the contents clearly and answer your questions accordingly.

Quantity I: Vipin can swim at 6 km/hr in still water. The river flows at 3 km/hr and it takes 8 hours more upstream then downstream for the same distance. How far is the place?

Quantity II: A man can row 25 km/hr in still water and the river is running at 15 km/hr. if the man takes 2 hr to row to a place and back, how far is the place?

The brother is elder to his sister by 6 years. Seven years ago the product of their ages was 72. What is the age of the brother?

If xy = -30 and x2 + y2 = 61, then find the value of (x + y).

If √(1 - sin2A) = x, then the value of x is

If O is the orthocentre of a triangle ABC and ∠BOC = 100°, the measure of ∠BAC is

P and Q are two alloys which are prepared by mixing tin and lead in the ratio of 12 : 5 and 4 : 3 respectively. If equal quantities of alloys are melted to form athird alloy R, then what is the ratio of tin and lead in alloy R?

A student multiplied a number by 3/10 instead of 10/3. What is the percentage error in the calculation?