15 POINTS TO PEOPLE WHO ANSWER CORRECTLY WITH EXPLINATION
6.Henry can finish painting a fence in 8 hours. John can finish painting the same fence in 12 hours. If they work together for 4 hours, how much of the fence is left unfinished?
They have finished 1/2+1/3=5/6. Explanation, if Henry finished in 8 hours that means he is halfway done because of 4 hours, for John he has finished 1/3 because 4/12 is 1/3. Let me know if you need anymore