Question 1193949
{{{system(7*r*1=1,and, 3*r*x=1)}}}


1, for the right-side member of both for both situations representing the "work", same value in each situation{{{(3x)/7=1/1}}};
{{{x=7/3}}}

{{{x=2&1/3}}}{{{hours}}}-------for just three girls to do this work.