Răspuns :
15×28+15×12-14×40 =
15 x (28 + 12) - 14 x 40 =
15 x 40 - 14 x 40 =
40 x ( 15 - 14) =
40 x 1 =
40
15 x (28 + 12) - 14 x 40 =
15 x 40 - 14 x 40 =
40 x ( 15 - 14) =
40 x 1 =
40