Question 295713
Around 2 hours 20 min  do this pretend sus an paints 1 pph or one paintstroke per hour so in 4 hours she does 4 paintstrokes and to paint the house you need to do four paintstroke james does 2/3 pph so that for every hour for every 20 min susan does 3/9of the stroke and james does 2/9 and the total painstroke needed is 36/9  by adding every twenty minutes you find u add 7 times or 2 hrs twenty mins
3/9*7=21/9
2/9*7=14/9
14/9+21/9=35/9 you want 36/9 so this is close enough good luck