Question

¿Cuál terna de números tiene una suma que NO es igual a $1$ ?

Which triplet of numbers has a sum NOT equal to $1?$

$(\frac12,\frac13,\frac16)$

$(2,-2,1)$

$(0.1,0.3,0.6)$

$(1.1,-2.1,1.0)$

$(-\frac32,-\frac52,5)$

A es igual a $\dfrac{3}{6} + \dfrac{2}{6} + \dfrac{1}{6} = 1.$

B se reduce a $2 - 2 + 1 = 1.$

C suma $.1 + .3 + .6 = 1.$

Sin embargo, D suma $1.1 - 2.1 + 1.0 = 0.$

Para asegurarnos, verificamos que E tiene una suma de $-\dfrac{8}{2} + 5 = 5 - 4 = 1.$

Por lo tanto, D es la respuesta correcta.

We have that A is the same as $\dfrac{3}{6} + \dfrac{2}{6} + \dfrac{1}{6} = 1.$

B reduces to $2 - 2 + 1 = 1.$

C adds up to $.1 + .3 + .6 = 1.$

D however adds to $1.1 - 2.1 + 1.0 = 0.$

To make sure, we check that E has a sum of $-\dfrac{8}{2} + 5 = 5 - 4 = 1.$

Thus, D is the correct answer.