Question
A tank can be filled by pipe A in 12 hours and by pipe B
in 18 hours. A waste pipe C can empty the full tank in 36 hours. If all three pipes are opened together, in how many hours will the tank be filled?Solution
A’s rate = 1/12 tank/hour B’s rate = 1/18 tank/hour C’s (waste) rate = −1/36 tank/hour Net rate = 1/12 + 1/18 − 1/36 LCM of 12, 18, 36 is 36: 1/12 = 3/36 1/18 = 2/36 1/36 = 1/36 Net = (3 + 2 − 1)/36 = 4/36 = 1/9 Time = 1 ÷ (1/9) = 9 hours Answer: 9 hours.
Each question is followed by three statements I, II and III. You have to decide whether the data given in the statements are sufficient to answer the qu...
How many students passed in first class?
I. 75% of the students who appeared in the examination have passed in first or second or third class....
The ratio of ages of A and B is 4:5 and that of B and C is 3:2. Find the age of B after 10 years.
Statement I: Difference between the ages of C ...
What was the price of House P last year?
Statement I: The ratio of the price of two houses P to Q was 3:4 last year.
Statement II: T...
How many people are there in a Train? Statement I: There are 225 females in the Bus. Statement II: 25% of passengers are males and 15% are children....
What is the speed of stream?
I Sum of time taken by a boat in upstream and downstream is 46 hrs to cover distance 460 km in each.
II...
In how much time can Pipe C empty the tank? Statement I: Pipes A and B can fill half the tank in 6 hrs 30 minutes. Statement II: Together with empty...
The question consists of two statements numbered “I and II” given below it. You have to decide whether the data provided in the statements are suici...
A trader allows two successive discounts of x% and y% on the marked price of an article. Is the selling price of the article less than Rs. 18,000?
<...Each question is followed by three statements I, II and III. You have to decide whether the data given in the statements are sufficient to answer the qu...
Relevant for Exams:
