If the area of a circle inscribed in a square is 9π $$ {}\ cm^2 $$, then the area of the square is

36 people working 8 hours a day can do 3 units of work in 12 days. How many persons are required to do 5 units of that work in 16 days. If they work for 6 hours a day?

The length of the common chord of two intersecting circles is 24 cm. If the diameter of the circles are 30 cm and 26 cm, then the distance between the center (in cm) is 

The respective ratio between the present ages of Rani and Moni is 6 : 7. If Moni is 4 years older than Rani, then what will be the respective ratio of the ages of Rani and Moni after 4 years? 

A shopkeeper marks an article 24% above its cost price and allows a 15% discount on the marked price. If he earns a profit of Rs. 27 by selling the article, then the selling price of the article is:

A solid sphere of diameter 7 cm is cut into two equal halves. What will be the increase (in cm.²) in the total surface area?

If the perimeter of a rectangle is 24cm with length being twice as its breadth, find its area.

Vaishnavi and Saurabh start moving at the same time from city A to city B, 60 km away. Vaishnavi travels 4 km/hr slower than Saurabh. Saurabh reaches city B and at once turns back meeting Vaishnavi, 12 km from city B. What is the speed of Vaishnavi ?