A and B can complete a task in seven days if they work together. A has a 13/4 efficiency advantage over B. A may complete the same task by herself in :
A. 9 1/3days
B. 11 days
C. 12 1/4days
D. 16 1/3days
Answer:B
A and B can complete a task in seven days if they work together. A has a 13/4 efficiency advantage over B. A may complete the same task by herself in :
A. 9 1/3days B. 11 days C. 12 1/4days D. 16 1/3days
Explanation: 7/4 : 1 = 7 : 4. (A's 1 day's work) : (B's 1 day's work) = 7 : 4.Allow 7x and 4x for A's and B's one-day work, respectively.Then 7x + 4x = 1/7 => 11x = 1/7 => x = 1/77.As a result, A's 1 day's work Equals ( 1/77 x 7 ) = 1/11.