Question

Baban takes 8 hours to do a job. Mahendra takes 10 hours to do the same Job. How long should it take both Baban and Mahendra, working together but independently, to do the same job?

• A. \(\frac{40}{11}\)
• B. \(\frac{40}{9}\)
• C. \(\frac{9}{40}\)
• D. 9

Answer 1

The Correct Option is B

Work Completion Calculation 

Step 1: Work Done by Each Person in One Hour

• Work done by Baban in 1 hour:

\[ \frac{1}{8} \]

• Work done by Mahendra in 1 hour:

\[ \frac{1}{10} \]

Step 2: Combined Work Done in One Hour

\[ \frac{1}{8} + \frac{1}{10} = \frac{5}{40} + \frac{4}{40} = \frac{9}{40} \]

Step 3: Time Taken to Complete the Job Working Together

\[ \text{Time} = \frac{1}{\frac{9}{40}} = \frac{40}{9} \]

Final Answer

Thus, working together, Baban and Mahendra will complete the job in \(\frac{40}{9}\) hours.