Question
Three pipes A, B and C are connected to a reservoir. Pipe A
can fill it in 16 minutes, pipe B can fill it in 24 minutes, while pipe C can empty the completely filled reservoir in 48 minutes. Pipe A is opened first, pipe B after 4 minutes, and pipe C after 8 minutes. Find the total time taken to fill the reservoir.Solution
Let the capacity of the reservoir be 48 litres. {LCM (16, 24 and 48)}
So, efficiency of inlet pipe A = 48 ÷ 16 = 3 litres/minute
And, efficiency of inlet pipe B = 48 ÷ 24 = 2 litres/minute
And, efficiency of outlet pipe C = 48 ÷ 48 = 1 litre/minute
In first 4 minutes, pipe A will fill 4 × 3 = 12 litres
And, pipes A and B together will fill 4 × (3 + 2) = 20 litres
So, required time = 4 + 4 + {(48 − 12 − 20) ÷ (3 + 2 − 1)}
= 8 + (16 ÷ 4) = 12 minutes
The present ages of Karan and Arjun are in the ratio 6 : 5, respectively. If 4 years ago from now, the sum of ages of Karan and Arjun was 36 years, the...
- Three years ago, the combined age of Pawan and Qureshi was 49 years. Currently, the ratio of their ages is 5:6. What will be Qureshi’s age four years fro...
Currently, Shweta and Rajni's ages are in the ratio of 5:4. Five years from now, the ages of Priya and Rajni will have a ratio of 7:5. Gautam is 10 year...
10 years ago age of A is as old B 6 years ago and Age of C after 7 years is 20 years. If present average age of them is 25 years, then find the sum of t...
Difference of ages of father and son is 24 years. Two years back age of father was twice the son's present age.
What is father's age now?
Two years ago, the ages of A, B, and C were x−6x - 6, x+10x + 10, and x+14x + 14 years respectively. If the average of their current ages is 38 years,...
The ratio between the present age of Beena and Meenal is 5:7, where Sumit is 6 years younger than Meenal then find the ratio of their ages 9 years hence.
Two years hence, the ratio of the ages of ‘B’ and ‘C’ will be 5:4. The present age of ‘C’ is half of the sum of the present ages of ‘A’...
A girl’s age is 160% of what it was 5 years ago, but 80% of what it will be after 6 years. What is her present age?
The present age of Surjeet and Rakesh are in the ratio of 4:5. After 8 years the ratio of their ages will be 6:7. What is 70% of the sum of their presen...