8 children and 12 men complete a certain piece of work in 9 days. If each child takes twice the time taken by a man to finish the work, in how many days will 12 men finish the same work ?

A. 6 days
B. 8 days
C. 10 days
D. 12 days

2 children = 1 man
(8 children + 12 men ) = 16 men
Now, less men, more days
12 : 16 : 9 : x
x = 16×9/12=12 days