1
5800 + 300 = 6100 8 + 3 = 11 2
4800 - 600 =4200
8-6=2 3
64 + 11 = 75 64 + (10+1) = 75 4
43 + 9 = 52 43 + (+10-1) = 52 5
43 + 19 = 62 43 + (+20-1) = 62 6
16 - 11 = 5 16 - (-10+1) = 5 7
46 - 21 = 25 76 - 31 = 45 8
16 - 9 = 7 16 - (-10+1) = 7
316 - 9 = 307 9
43 -1 9 = 24 83 -29 = 54 10
856 + 101 = 957 856 +100 +1 = 957 11
856 - 201 = 1057 856 - 301 = 1157 12
856 + 99 = 955 856 +(+100-1) = 955 13
856 + 199 =1055 456 + 299 = 755 14
856 + 101 = 957 856 +100 +1 = 957 15
856 + 201 = 1057
16
246 - 99 = 147 246 - (100+1) = 147 17
246 - 199 = 47 646 - 199 = 447 18
27 x 10 = 270 46 x 100 = 4600 65 x 1000 = 65000 19
2 x 60 = 120 6 x 200 = 1200 5 x 3000 = 15000 20
200 10 = 20 2 1=1 3000 10 = 300 21
200 100 = 2 2 1=1 3000 1000 = 3 22
60 20 = 3 400 200 = 2 16000 8000 = 2 23
198 + 37+2 =237 198 + 2 =237 200 + 37 =237 24
170 + 67+30 =267 170 + 30 =200 200 + 67 =267 25
40 x 600 =24000 4 x 6 =24 26
5 x 7 x 8 = 280 5 x 8 =40 40 x 7 =280 27
4,7 x 10 =47 4,7 x 100 =470 4,7 x 1000 =4700 28
234 10 = 23,4 476 100 = 4,76 6325 1000 = 6,325 29
20 2 = 10 2 1=1 246 2= 123 30
74 2 = 37 70 2 = 35 4 2= 2 35 + 2 = 37
31
840 20 = 42 840 10 = 84 84 2 = 42 32
46 x 5 =230 46 x 10 =460 460 2 = 230 33
46 x 50 =2300 46 x 100 =4600 460 2 = 2300 34
310 5 = 62 310 10 =31 31 x 2 = 62 35
1800 50 = 36 1800 100 =18 18 x 2 = 36 36
1/4 de 12 =3 12 4 =3 37
2/3 de 12 = 12 2 x 12 = 24 24 2 = 12 38
10% de 85 = 12 85 10 = 8,5 39
3% de 9 = 0,27 3 x 9 = 27 27 100 = 0,27 40