Question

18 men can complete a piece of work in 63 days. 9 women take 189 days to complete the same piece of work. How many days will 9 men, 9 women and 12 children together take to complete the piece of work if 7 children alone can complete the piece of work in 486 days?

Answer 1

Its not a simple one

Answer 2

Answer:

60 days

Step-by-step explanation:

18 men can complete a work in 63 days

So, 1 man can complete part of work in 1 day = $\frac{1}{63 \times 18}$

                                                                           = $\frac{1}{1134}$

So, 9 men can complete part of work in 1 day = $\frac{9}{1134}$

9 women take 189 days to complete the same piece of work.

So, 1 woman can complete part of work in 1 day = $\frac{1}{189 \times 9}$

                                                                           = $\frac{1}{1701}$

So, 9 women can complete part of work in 1 day = $\frac{9}{1701}$

7 children alone can complete the piece of work in 486 days

So, 1 child can complete part of work in 1 day = $\frac{1}{486 \times 7}$

                                                                           = $\frac{1}{3402}$

So, 12 children can complete part of work in 1 day = $\frac{12}{3402}$

So, 9 men, 9 women and 12 children can do a part of work in 1 day:

=  $\frac{9}{1134}+\frac{9}{1701}+\frac{12}{3402}$

=  $\frac{19}{1134}$

So, 9 men, 9 women and 12 children can do complete  work in days = $\frac{1134}{19}=59.6$

Hence 9 men, 9 women and 12 children can do complete work in 60 days