Question 880119
If Jake and Paul plant 6 trees in .6 hours, it takes .1 hours x 2 men, or .2 man-hours per tree.
*Assuming* that the rate of work by Jake and Paul are the same, then Paul plants trees at the rate of .6 man-hours per tree.
.6 man-hours * 35 trees = 21 hours for Paul to plant 35 trees.