Question:
Three pipes A, B and C can fill a tank from empty to full in 30 minutes, 20 minutes, and 10 minutes respectively. When the tank is empty, all the three pipes are opened. A, B and C discharge chemical solutions P,Q and R respectively. What is the proportion of the solution R in the liquid in the tank after 3 minutes?
[A].
Three pipes A, B and C can fill a tank from empty to full in 30 minutes, 20 minutes, and 10 minutes respectively. When the tank is empty, all the three pipes are opened. A, B and C discharge chemical solutions P,Q and R respectively. What is the proportion of the solution R in the liquid in the tank after 3 minutes?
[A].
| 5 |
| 11 |
[B].
| 6 |
| 11 |
[C].
| 7 |
| 11 |
[D].
| 8 |
| 11 |
Answer: Option B
Explanation:
| Part filled by (A + B + C) in 3 minutes = 3 | 1 | + | 1 | + | 1 | = | 3 x | 11 | = | 11 | . | ||||
| 30 | 20 | 10 | 60 | 20 |
| Part filled by C in 3 minutes = | 3 | . |
| 10 |
| Required ratio = | 3 | x | 20 | = | 6 | . | ||
| 10 | 11 | 11 |