A, B and C can complete a work in 10, 20 and 30 days respectively. If D can destroy the same work in 15 days. Find the time taken by all of them to complete the whole work.

Directions: The Pie chart given here represents the domestic expenditure of a family in per cent. Study the chart and answer the following questions if the total monthly income of the family is ₹ 33,650.

A: Expenditure on food

B: Expenditure on house-rent

C: Expenditure on entertainment

D: Expenditure on education and maintenance of children

E: Medical and miscellaneous expenditure

F: Deductions towards provident fund

After provident fund deductions and payment of house rent, the total monthly income of the family remains

Direction: Each of the questions consists of a question and two statements numbered I and II given below it. You have to decide whether the data provide in the statements are sufficient to answer the question. Read both the statements and Give answer.
(A) If the data in statement I alone are sufficient to answer the question, while the data in statement II alone not sufficient to answer the question;
(B) If the data in statement II alone are sufficient to answer the question, while the data in statement I all are not sufficient to answer the question;
(C) If the data either in statement I alone or in statement II alone are sufficient to answer the question;
(D) If the data even in both statements I and II together are not sufficient to answer the question;
(E) If the data in both statements I and II together are necessary to answer the question.

Five years ago, what was the ratio between the age of Sonu and Monu?
 I. Ratio between present age of Sonu and Monu is 3: 2.
II. Ratio between present age of Sonu and Ramu is 4 : 3.

Direction : Each of the questions below consists of a question and three statements numbered I, II and III given below it. You have to decide whether the data provided in the statements are sufficient to answer the question. 

Area of a square is equal to the area of a circle. What is the circumference of the circle?
I. The diagonal of the square is 8 inches.
II. The side of the square is 12 inches.

In a triangle ΔABC, the sides DE parallel to BC and AD = 6 cm, DB = 9 cm, AE = 8 cm, find the value of AC.

The speed of a boat in still water is 10 km/h. The speed of the stream is 2 km/h. What is the total distance that the boat will travel if it is rowed for 4 hours upstream and 3 hours downstream?

The pipe can fill a tank in 36 minutes and the another pipe can empty it in 45 minutes. If both pipes are opened simultaneously, the time (in hours) it takes to fill half the capacity of the tank is: