<PRE><B>Question 334606</B>
a painting job can be completed by 7 painters in 17 days.
 if 21 more painters joined the team 9 days after starting work on the job,
 then how many more days are required to complete the job?
:
Find out how many man-days to complete the job
7 * 17 = 119 man-days
:
Let d = no. of days to finish the job
:
there will be 28 total painters after the 1st 9 days
:
(7*9) + (28d) = 119
:
63 + 28d = 119
:
28d = 119 - 63
:
28d = 56
d = {{{56/28}}}
d = 2 days to finish the job
;
;
Check solution
(7*9) + (28*2) = 
63 + 56 = 119
</PRE>