Question

Two pipes A and B can fill a tank Win 24 minutes and 32 minutes respectively. If both the pipes are opened simultaneously, after how much time should B be closed so that the tank is full in 18 minutes? ​

Answer 1

Let the total capacity of the tank be 96 units (LCM of 24 & 32).

A fills = 2496 = 4 units / minute.

B fills = 3296 = 3 units / minute.

Let the time for which B is opened is x minutes.

According to the question, 4 × 18 + 3 × x = 96

3x = 96 - 72 = ⇒ 3x = 24

x = 8 minutes.

The pipe B should be closed after 8 minutes.

Answer 2

Answer:

Step-by-step explanation:

Let the total capacity of the tank be 96 units (LCM of 24 & 32).

A fills =  

96/24 = 4 units / minute.

B fills =  

96/32= 3 units / minute.

Let the time for which B is opened is x minutes.

According to the question, 4 × 18 + 3 × x = 96

3x = 96 - 72 = ⇒ 3x = 24

x = 8 minutes.

The pipe B should be closed after 8 minutes.