Answer:
clerk A and clerk B can simultaneously stock a shelf in [tex]\frac{180}{13}[/tex] minutes
Explanation:
Let the first clerk be A and the second clerk be B
A can stock a shelf in 20 min
B can stock a shelf in 45 min
Consider the complete work to be W
A’s rate of stocking = [tex]\frac{W}{20}[/tex] per minute
B’s rate of stocking = [tex]\frac{W}{45}[/tex] per minute
When, A and B work simultaneously, rate of work done = [tex]\frac{W}{20}+\frac{W}{45}[/tex]
Total work done simulatenously = [tex]\frac{W}{\frac{W}{20}+\frac{w}{45}}[/tex]
=[tex]\frac{20 * 45}{20+45}[/tex]
Therefore, clerk A and clerk B can simultaneously stock a shelf in [tex]\frac{180}{13}[/tex] minutes
