If the length of a rectangle is increased by 20% and its breadth is decreased by 20%, its area:

10 persons can do a job in X days. If 20 persons with twice the efficiency can do the same job in 5 days, then find the value of X?

 A can do a piece of work alone in 30 days. B is 25% less efficient than A, while C is $$33{1\over 3}$$ % more efficient than B. In how many days can A, B and C, working together, complete the work?

What is the perimeter of a square inscribed in a circle of radius 5 cm?

Directions: Find the wrong number in the following number series:

141, 156, 147, 162, 153, 165, 159

The ages of Bholu and Nitesh are in the ratio of 8 : 7 respectively. After 6 years, the ratio of their ages will be 19 : 17. What is the difference in their ages?

The graphs of the equations 3x + y-5=0 and 2x- y -5=0 intersect at the point P(α,β).  What is the value of (3α + β)?

The sum of the digits of a two digit number is 15. When 9 is subtracted from the given number then its digits interchanged. What will be the required original number?