Quantitative Aptitude - Arithmetic Ability Questions

If ax + by = 1 and bx + ay = 2aba2+b2 then x2+y2a2+b2 is equal to

The difference between cost price and selling price is Rs 221. If profit percentage is 17%, then what is the selling price (in Rs)?

The ratio of present ages of Ramita and Satyajit is 9:7. After 9 years the ratio of their ages will be 5:4. What is Ramita's present age?

The average of 21 numbers is 12. The average of the first 11 numbers is 9 and the average of the last 11 numbers is 15. What is the value of the middle number?

The reciprocal of the sum of the reciprocals of 3/8 and 8/11 is:

If 3x^2 + ax + 4 is perectly divisible by x - 5, then the value of a is :

If cos 240° = x, then value of x is

What is the value of cos2A/(1 + sinA)?