A's 1 day's work = \(\frac{1}{15};\)

B's 1 day's work = \(\frac{1}{20};\)

(A + B)'s 1 day's work = \(\left(\frac{1}{15}+\frac{1}{20}\right)= \frac{7}{60}.\)

(A + B)'s 4 day's work = \(\left(\frac{7}{60}\times4\right)= \frac{7}{15}.\)

Therefore, Remaining work  =  \(\left(1-\frac{7}{60}\right)= \frac{8}{15}.\)

\(9\frac{1}{5}days\)(A + B + C)'s 1 day's work =  \(\frac{1}{4}, \)

A's 1 day's work = \(\frac{1}{16},\)

B's 1 day's work = \(\frac{1}{12}.\)

So, C's 1 day's work = \(\frac{1}{4}-\left(\frac{1}{16}+\frac{1}{12}\right)= \left(\frac{1}{4}-\frac{7}{48}\right)=\frac{5}{48}\)

So, C alone can do the work in \(\frac{48}{5}=9\frac{3}{5}days\)

A's 2 day's work = \(\left(\frac{1}{20}\times2\right)=\frac{1}{10}.\)

(A + B + C)'s 1 day's work = \(\left(\frac{1}{20}+\frac{1}{30}+\frac{1}{60}\right)=\frac{6}{60}=\frac{1}{10}.\)

Work done in 3 days = \(\left(\frac{1}{10}+\frac{1}{10}\right)=\frac{1}{5}\)

Now, \(\frac{1}{5}\) work is done in 3 days.

So, Whole work will be done in (3 x 5) = 15 days.

Ratio of times taken by A and B = 1 : 3.

The time difference is (3 - 1) 2 days while B take 3 days and A takes 1 day.

If difference of time is 2 days, B takes 3 days.

If difference of time is 60 days, B takes  \(\left(\frac{3}{2}\times60\right)\) = 90 days.

So, A takes 30 days to do the work.

A's 1 day's work = \(\frac{1}{30}\)

B's 1 day's work = \(\frac{1}{90}\)

(A + B)'s 1 day's work =  \(\left(\frac{1}{30}+\frac{1}{90}\right)=\frac{4}{90}=\frac{2}{45}.\)

A and B together can do the work in \(\frac{45}{2}=22\frac{1}{2}days\)

C's 1 day's work = \(\frac{1}{3}-\left(\frac{1}{6}+\frac{1}{8}\right)=\frac{1}{3}-\frac{7}{24}=\frac{1}{24}.\)

A's wages : B's wages : C's wages =  \(\frac{1}{6}:\frac{1}{8}:\frac{1}{24}=4:3:1.\)

So, C's share (for 3 days) = Rs. \(\left(3\times\frac{1}{24}\times3200\right)\)   = Rs. 400.