Вправи: 23

23. Обчисли зручним для тебе способом.

12 + 24 + 8 = 12 + 8 + 24 = 20 + 24 = 44;

172 – (52 + 49) = 172 – 52 – 49 = 120 – 50 + 1 = 71;

(35 + 70) : 7 = 35 : 7 + 70 : 7 = 5 + 10 = 15;

160 + (70 + 140) = 160 + 140 + 70 = 300 + 70 = 370;

75 + 75 + 75 + 75 = (50 + 25) • 4 = 200 + 100 = 300;

(18 + 43) + 22 = 18 + 22 + 43 = 40 + 43 = 83;

25 • 7 • 4 = 25 • 4 • 7 = 100 • 7 = 700;

5 • 78 • 2 = 78 • 5 • 2 = 78 • 10 = 780;

(27 + 26) – 17 = 27 – 17 + 26 = 10 + 26 = 36.