84 persons take 56 days to complete a certain task. When one-fourth of the task was completed, one-seventh of the workers left. How many days in all does it take to complete the entire task?
The amount obtained by investing a certain sum at r% p.a. for 3 years at simple interest is equal to the simple interest on the same sum at the same rate for 13 years. The value of r is:
The average of 18 numbers is 65. The average of the first 10 numbers is 72 and that of the last 9 numbers is 58. If the 10th number is excluded, then what is the average of the remaining numbers (correct to one decimal place)?
The ratio of A and B is 2 : 3, and B is 8 more than A. If a certain number k is added to each of A and B, then the ratio becomes 7 : 9. The value of k is:
Pipes A and B can fill a tank in 8 hours and 12 hours, respectively. C is an outlet pipe. When all the three are opened together, the tank is filled in 13(1/3) hours. C alone can empty the full tank in:
A sum of Rs. 3,780 is divided between A, B and C such that if their shares are decreased by Rs. 130, Rs. 150 and Rs. 200, respectively, then they are in the ratio of 5 : 2 : 4. What is the original share of C?
The ratios of acid and water in the solutions in vessels A and B are 4 : 5 and 5 : 1, respectively. A new solution is obtained by mixing 5 litres and 4 litres of the solutions from A and B, respectively. What is the ratio of acid and water in the new solution?
