Two inlet pipes, A and B, can fill an empty cistern in 22 and 33 hours, respectively. They were opened at the same time, but pipe A had to be closed 3 hours before the cistern was full. How many hours in total did it take the two pipes to fill the cistern?
(a)15
(b)17
(c)14.2
(d)16

Options

A. 15
B. 16.2
C. 14.2
D. 16

Answer

A