Quantitative Aptitude - Arithmetic Ability Questions

If x + y = 10 and x2 + y2 = 68, then find xy

If x+y+z = 1, 1/x + 1/y + 1/z = 1 and xyz = -1, then x3+y3+z3 is equal to

If Cosec θ = 17/8, then Cot θ = ?

The mean of marks secured by 65 students in division A of class X is 54, 30 students of division B is 50 and that of 55 students of division C is 48. Find the mean of marks of the students of three divisions of Class X.

In the given figure, ∠QRN = 40°, ∠PQR = 46° and MN is a tangent at R. What is the value (in deg) of x, y and z respectively?

A invested an amount of x rupees in a bank for 2 years which gave 5% interest in year 1 and 6% interest in year 2. The amount received after 2 years is Rs 24,486. What is the value of x?

An alloy is made by mixing metal A costing Rs 2000/kg and metal B costing Rs 400/kg in the ratio A:B = 3:1. What is the cost (in Rs) of 8 kilograms of this alloy?

What is the unit digit of 15+25+35+...+205 ?