Pipe A can fill a tank in 4 hours and pipe B can fill it in 6 hours. If they are opened on alternate hours and If pipe A is opened first, in how many hours,the tank shall be full
1). $4\frac{1}{2}$
2). $3\frac{1}{2}$
3). $3\frac{1}{4}$
4). $4\frac{2}{3}$
A tank has two pipes. The first pipe can fill it in 4 hours and the second can empty it in 16 hours. If two pipes be opened together at a time, then the tank will be filled in
1). $5\frac{1}{2}$ hours
2). 10 hours
3). 6 hours
4). $5\frac{1}{3}$ hours
Three pipes A. B and C can fill a tank in 6 hours. After working together for 2 hours, C is closed and A and B can fill the remaining part in 7 hours. The number of hours taken by C alone to fill the tank is
1). 10
2). 12
3). 14
4). 16
A pipe can fill a cistern in 9 hours. Due to a leak in its bottom, the cistern fills up in 10 hours. If the cistern is full, in how much time will it be emptied by the leak
1). 70 hours
2). 80 hours
3). 90 hours
4). 100 hours
Three pipes A, B and C can fill a tank in 6 hours. After working together for 2 hours C is closed and A and B fill the tank in 8 hours. The time (in hours) in which the tank can be filled by pipe C alone is
1). 10
2). 12
3). 8
4). 9