Two Pipes A And B Can Fill A Tank In 9 Hours And 3 Hours Respectively

1.	Two Pipes A And B Can Fill A Tank In 9 Hours And 3 Hours Respectively. If They Are Opened On Alternate Hours And If Pipe A Is Opened First, In How Many Hours Will The Tank Be Full?
Answer» Tank part FILLED by pipe A in 1 hour =1/9 Tank part filled by pipe B in 1 hour =1/3 Given Pipe A and B are opened alternatively. So Part filled in every 2 HOURS =(1/9+1/3)=4/9 Tank Part will be filled in 4 hour =24/9=8/9 Remaining part = (1-8/9)=1/9 So NEXT is A TURN. So Pipe A will fill remaining 1/9 part in next 1 hour. Total Time = (4 hrs + 1 hrs) = 5 hrs. Tank part filled by pipe A in 1 hour =1/9 Tank part filled by pipe B in 1 hour =1/3 Given Pipe A and B are opened alternatively. So Part filled in every 2 hours =(1/9+1/3)=4/9 Tank Part will be filled in 4 hour =24/9=8/9 Remaining part = (1-8/9)=1/9 So next is A turn. So Pipe A will fill remaining 1/9 part in next 1 hour. Total Time = (4 hrs + 1 hrs) = 5 hrs.

Two Pipes A And B Can Fill A Tank In 9 Hours And 3 Hours Respectively. If They Are Opened On Alternate Hours And If Pipe A Is Opened First, In How Many Hours Will The Tank Be Full?

Answer»

Tank part FILLED by pipe A in 1 hour =1/9

Tank part filled by pipe B in 1 hour =1/3

Given Pipe A and B are opened alternatively.

So Part filled in every 2 HOURS =(1/9+1/3)=4/9

Tank Part will be filled in 4 hour =2*4/9=8/9

Remaining part = (1-8/9)=1/9

So NEXT is A TURN.

So Pipe A will fill remaining 1/9 part in next 1 hour.

Total Time = (4 hrs + 1 hrs) = 5 hrs.

Tank part filled by pipe A in 1 hour =1/9