Найди значения выражений, используя прием последовательного умножения и деления.
1)
25 * 40;
75 * 20;
15 * 80;
15 * 28;
16 * 25;
36 * 20;
25 * 32;
35 * 24;
16 * 15;
45 * 12;
18 * 15;
25 * 64;
48 * 15;
55 * 12;
24 * 50.
2)
450 : 6;
327 : 9;
288 : 8;
270 : 18;
360 : 45;
432 : 48;
240 : 16;
210 : 15;
315 : 45;
690 : 15;
432 : 54;
385 : 55;
1000 : 20;
1000 : 25;
1000 : 50.
25 * 40 = (20 + 5) * 40 = 20 * 40 + 5 * 40 = 800 + 200 = 1000
75 * 20 = (70 + 5) * 20 = 70 * 20 + 5 * 20 = 1400 + 100 = 1500
15 * 80 = (10 + 5) * 80 = 10 * 80 + 5 * 80 = 800 + 400 = 1200
15 * 28 = (10 + 5) * (20 + 8) = 10 * 20 + 5 * 20 + 10 * 8 + 5 * 8 = 200 + 100 + 80 + 40 = 300 + 120 = 420
16 * 25 = (10 + 6) * (20 + 5) = 10 * 20 + 6 * 20 + 10 * 5 + 6 * 5 = 200 + 120 + 50 + 30 = 320 + 80 = 400
36 * 20 = (30 + 6) * 20 = 30 * 20 + 6 * 20 = 600 + 120 = 720
25 * 32 = (20 + 5) * (30 + 2) = 20 * 30 + 5 * 30 + 20 * 2 + 5 * 2 = 600 + 150 + 40 + 10 = 750 + 50 = 800
35 * 24 = (30 + 5) * (20 + 4) = 30 * 20 + 5 * 20 + 30 * 4 + 5 * 4 = 600 + 100 + 120 + 20 = 700 + 140 = 840
16 * 15 = (10 + 6) * (10 + 5) = 10 * 10 + 6 * 10 + 10 * 5 + 6 * 5 = 100 + 60 + 50 + 30 = 100 + 110 + 30 = 210 + 30 = 240
45 * 12 = (40 + 5) * (10 * 2) = 40 * 10 + 5 * 10 + 40 * 2 + 5 * 2 = 400 + 50 + 80 + 10 = 450 + 90 = 540
18 * 15 = (10 + 8) * (10 + 5) = 10 * 10 + 8 * 10 + 10 * 5 + 8 * 5 = 100 + 80 + 50 + 40 = 180 + 90 = 270
25 * 64 = (20 + 5) * (60 + 4) = 20 * 60 + 5 * 60 + 20 * 4 + 5 * 4 = 1200 + 300 + 80 + 20 = 1500 + 100 = 1600
48 * 15 = (40 + 8) * (10 + 5) = 40 * 10 + 8 * 10 + 40 * 5 + 8 * 5 = 400 + 80 + 200 + 40 = 600 + 120 = 720
55 * 12 = (50 + 5) * (10 + 2) = 50 * 10 + 5 * 10 + 50 * 2 + 5 * 2 = 500 + 50 + 100 + 10 = 600 + 60 = 660
24 * 50 = (20 + 4) * 50 = 20 * 50 + 4 * 50 = 1000 + 200 = 1200
450 : 6 = (420 + 30) : 6 = 420 : 6 + 30 : 6 = 70 + 5 = 75
327 : 9 = (300 + 27) : 9 = 300 : 9 + 27 : 9 = 33 (ост.3) + 3 = 36 (ост.3)
288 : 8 = (240 + 48) : 8 = 240 : 8 + 48 : 8 = 30 + 6 = 36
270 : 18 = (180 + 90) : 18 = 180 : 18 + 90 : 18 = 10 + 5 = 15
360 : 45 = (180 + 180) : 45 = 180 : 45 + 180 : 45 = 4 + 4 = 8
432 : 48 = (240 + 192) : 48 = 240 : 48 + 192 : 48 = 5 + 4 = 9
240 : 16 = (160 + 80) : 16 = 160 : 16 + 80 : 16 = 10 + 5 = 15
210 : 15 = (150 + 60) : 15 = 150 : 15 + 60 : 15 = 10 + 4 = 14
315 : 45 = (90 + 225) : 45 = 90 : 45 + 225 : 45 = 2 + 5 = 7
690 : 15 = (600 + 90) : 15 = 600 : 15 + 90 : 15 = 40 + 6 = 46
432 : 54 = (108 + 324) : 54 = 108 : 54 + 324 : 54 = 2 + 6 = 8
385 : 55 = (110 + 275) : 55 = 110 : 55 + 275 : 55 = 2 + 5 = 7
1000 : 20 = 100 : 20 * 10 = 5 * 10 = 50
1000 : 25 = 100 : 25 * 10 = 4 * 10 = 40
1000 : 50 = 100 : 50 * 10 = 2 * 10 = 20