This looks like another trap. Rather than blindly rushing in and calculate, try rearranging things:
( 4, -5, 6.2 ) + ( -43.132, 13.6, 86.5 ) - ( 4, -5, -4.8 ) = ( 4, -5, 6.2 ) + ( -43.132, 13.6, 86.5 ) + ( -4, 5, 4.8 ) = ( 4, -5, 6.2 ) + ( -4, 5, 4.8 ) + ( -43.132, 13.6, 86.5 ) = ( 0, 0, 11 ) + ( -43.132, 13.6, 86.5 ) = (-43.132, 13.6, 97.5 )
You would probably skip a few steps if you were doing this mentally.
Do a few more practice problems before you move on.
What is the sum of the following three displacements:
d = ( -12.4, 14.8, 0.0 )T e = ( 6.2, -10.2, 17.0 )T f = ( 6.2, -4.6, -17.0 )T