CALCULO MENTAL 4º
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Transcript of CALCULO MENTAL 4º
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45 + 30 = 75
4 + 3 = 75
412 + 300 = 712
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43 - 30 = 13
4 - 3 = 13539 - 300 = 239
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413 + 30 = 443
1 + 3 = 4
4213 + 30 = 4243
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463 - 30 = 433
6 - 3 = 3
4253 - 30 = 4223
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27 x 10 = 270
46 x 100 = 4600
65 x 1000 = 65000
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2 x 60 = 120
6 x 200 = 1200
5 x 1000 = 5000
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20 x 60 = 1200
60 x 200 = 12000
50 x 1000 = 50000
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43 x 2 =86
14 x 20 =280
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20 10 = 2
2 1 = 1
300 10 = 30
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200 100 = 2
2 1 = 1
3000 1000 = 3
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20 2 = 10
2 1 = 1
246 2= 123
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164 + 11 = 175
164 + (10+1) = 175
3216 + 11 = 3327
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16 + 9 = 2516 + (+10-1) = 25
316 + 9 = 325
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16 - 11 = 5
16 - -10-1) = 27
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16 - 9 = 716 - (-10+1) = 27
316 - 9 = 307
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23 + 36 =59
(2+3)=5 (3+6)=9
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37 + 53 =90
(3+5)=8+1 (7+3)=10
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16 + 21 = 27
16 + (20+1) = 27
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16 + 31 = 47
16 + (30+1) = 47
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16 + 41 = 57
16 + (40+1) = 57
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16 + 19 = 35
16 + (20-1) = 35
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16 + 29 = 45
16 + (30-1) = 45
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16 + 39 = 55
16 + (40-1) = 55
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56 - 21 = 35
56 - (20-1) = 35366 - 21 = 345
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56 - 31 = 25
56 - (30-1) = 25366 - 31 = 335
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56 - 19 = 37
56 - (20+1) = 37366 - 19 = 347
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856 + 101 = 957
856 +100 +1 = 957
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856 + 201 = 1057
856 +200 +1 = 1057
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856 + 301 = 1157
856 +300 +1 = 1157
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246 - 99 = 147246 - (100+1) = 147
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646 - 199 = 447
646 - (-200+1) = 447
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1446 - 299 = 1147
1446 - (-300+1) = 1147