Question 774578
More information is needed.  You can make a generalized solution but you cannot answer anything specific without the missing information to be included.

Two men and three women.  Rates?
Four men and three women.  Rates?  Number of days? 


The description seems like uniform rates work problem.  The first group is a mixture of rates.  The second group is a different mixture of rates.  If you knew the time for both jobs, then you could determine the rates of man and woman.  If you knew rates of man and woman, then you could find time to do the job.  


Let r = man's rate
Let R = Woman's rate
Let d = time in days needed for the 4 men + 3 women


The problem description is formalized into this:
{{{2r*10+3R*10=1}}} AND {{{4r*d+3R*d=1}}} which are the needed equation for a system.


If r and R were known, then {{{d=1/(4r+3R)}}}.
If r were known but R were unknown, then you solve the 10-day equation for R and substitute this into the d formula equation and find d.
If r were UNKNOWN but R were..., you do what you need...