The first answer is going to be 15.42 (so b) and the second is going to be 10.67 (so a)
9.4 Ft for the first one
7.5 Ft for the second piece
12 Ft for the Third
he uses 5.2 Ft from the first piece of wood so 9.4 - 5.2= 4.6ft
he uses 6.1 ft from the second piece of wood , 7.5 - 6.1 = 1.4 ft
Nathan didnt use any of the 3rd piece of wood , so he still have 12 Feet of wood remaining so, 12+4.6+1.4 = 18 feet of wood left that he didnt use.
