# Ten men working for 6 days can co plete 5 copoes of a book.If there are 8 men working to complete 4 copies of the book, how many days will it take?

So total effort put is 10* 6 man days = 60 man days are needed to complete 5 copies of a book

8 men working x days complete 4 copies of a book

thus 8x man days are needed for completing 4 copies of a book

No of Man days is directly proportional to the number of copies of the book because more the man days more the copies of the book

60 mandays results in 5 copies thus

1 copy in 60/5 = 12 man days

4 copies in 4*12 mandays = 48 mandays

Thus 8 people working x days put in 8x man days to complete 4 copies of the book

and 8x = 48

x = 6

thus 6 days are needed by 8 people to complete 4 copies