Question 1151307
R*t=Q
R, the rate
t, time in days
Q, amount of work done


r, the rate of work for 1 worker
x, unknown time in days


{{{system(10r*3=2,(10+5)rx=9)}}}


-


{{{system(30r=2,15rx=9)}}}


{{{(15rx)/(30r)=9/2}}}


{{{x/2=9/2}}}


{{{highlight(x=9)}}}