Question 795806
Derrick contributes 1/6 of an hour in an hour
Darren does all the chores in half the time as Derrick means Darren contributes 1/3 of an hour in an hour since he does all chores in 6/2 hours
Daniel takes 3 +1 hours to do chores and contributes 1/4 of an hour in an hour
therefore we have
1/6 +1/3 +1/4 = 1/t
2/12 +4/12 +3/12 = 1/t
9/12 = 1/t
t = 12/9 = 4/3
t = 1 hour and 20 minutes