Quantitative Aptitude - Arithmetic Ability Questions

a, b and c are 3 values, such that a + b = 5, b + c = 7.5 and c + a = 8.5. What will be the average of these values?

The mean of 12 observations is 15. One more observation is included and the new mean becomes 16. The 13th observation is

The sum of the ages of Rohit and Ankit is 78. Rohit's age is twice the age of Ankit. What is the age (in years) of Rohit?

Two numbers are 10% and 20% lesser than a third number respectively. By how much percent is the second number should be enhanced to make it equal to the first number?

If Mr. Raghav taught a total of 500 hours, then what is the difference in number of hours of teaching algebra and modern Maths?

What is the equation of a line which has 3 as x-intercept and -5 as y-intercept?

What is the value of (cos45° + 1/3) ?

If the cost of 17 m of cloth is Rs. 77 5/7, find its cost per meter in Rs.?