Question

cate numere de forma x1yz sunt divizibile cu 2

Answer 1

$\overline{x1yz} \: \: \vdots \: \: 2 = > z \: \in \: \left \{ 0,2,4,6,8 \right \}$

$x \: \in \: \left \{ 1,2,3,4,5,6,7,8,9\right \}$

$y \: \in \: \left \{ 0,1,2,3,4,5,6,7,8,9\right \}$

$x \: \mapsto \: 9 \: posibilitati$

$y \: \mapsto \: 10 \: posibilitati$

$z \: \mapsto \: 5 \: posibilitati$

$9 \times 10 \times 5 = 450 \: numere$