So lets say the distance one boy travels is 'x', you can set up an equation like this: x + x + 1 = 7 2x +1 = 7 2x = 6 x = 3 So one boy walks 3 miles in one hour, and the other walks 4 miles in one hour. Therefore, their speeds are 3 miles per hour and 4 miles per hour respectively.
It neve mentions how much of his farm he uses, but assuming he uses all of it area=base times height given base=4.2 height=3 area=4.2 times 3 area=12.6 square kilometers
