Question 121068
Aaron's rate + Karen's rate = combined rate
(1 house / 12 hrs) + (1 house / 6 hrs) = 1 house / x hours
{{{1/12 + 1/6 = 1/x}}}
multiply both sides of the equation bt 12
{{{1 + 2 = 12/x}}}
{{{x = 12/3}}}
{{{x = 4}}}hrs answer