Q7 of 47 Page 176

A can finish a piece of work in 12 hours while B can finish it in 15 hours. How long will both take to finish it, working together?

Number of hours A required do a piece of work: 12


Number of hours B required do a piece of work : 15


Work done by A in one hour:


Work done by B in one hour:


Work done by A and B together in one hour: = =


They can do the work together in hours = 6hours.

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