Quantitative Aptitude - Arithmetic Ability Questions

The number of solutions of the pair of linear equations x + 2y - 8 = 0 and 2x + 4y = 16 is

If a + b = 10 and ab- 13 = -ba - 11, then what is the value of 3ab + 4a2 + 5b2 ?

If 9x - 6(3 - x) = 12, then the value of x is

For what value of 'y', x2 + 112x + y2 is a perfect square?

The value of -3+3+87+43 is

If x stands for addition, / stands for subtraction, + stands for multiplication and - stands for division, then what is the value of 20 x 8 / 8 - 4 + 2 ?

The mean of marks secured by 35 students in division A of class X is 65, 45 students of division B is 61 and that of 70 students of division C is 59. What is the mean of marks of the students of three divisions of Class X?

If √20 + √125 = 15.65, then what is the value of √45 + √5?