The correct option is B 13th part
Let the amount of work done by Eleanor be x part in a day.
And, the amount of work done by Madison be y part in a day.
The efficiency of Eleanor is double that of Madison.
∴x=2y ... (a)
In 6 days, Eleanor will complete 6x part, and Madison will complete 6y part.
Also, in 6 days, the work is completed.
The whole work is represented by 1.
∴6x+6y=1 ...(b)
Substitute equation (a) in (b).
6x+6y=1
⇒6(2y)+6y=1
⇒18y=1
⇒y=118
∴ In a day, Madison comletes 118th part of the work.
⇒ In 6 days, Madison completes 118th×6=13th part of the work.