Which triplet of numbers has a sum NOT equal to 1?
$\text{(A)}\ (1/2,1/3,1/6) \qquad \text{(B)}\ (2,-2,1) \qquad \text{(C)}\ (0.1,0.3,0.6) \qquad \text{(D)}\ (1.1,-2.1,1.0) \qquad \text{(E)}\ (-3/2,-5/2,5)$
By adding each triplet, we can see that $\boxed{(D)}$ gives us $0$, not $1$, as our sum.