Răspuns :
2 × 9 × 3 = (2 x 3) x 9 = 6 x 9 = 54 → asociativitate (proprietate a inmultirii)
3 × 1 × 7 = (3 x 1) x 9 = 3 x 9 = 27
9 × 5 × 2 = 9 x ( 5 x 2 ) = 9 x 10 = 90
3 × 1 × 7 = (3 x 1) x 9 = 3 x 9 = 27
9 × 5 × 2 = 9 x ( 5 x 2 ) = 9 x 10 = 90