Question

Tính nhẩm:

a) 27 × 10 = …...;   72 × 100 =…...;   14 × 1000 =…...

86 × 10 = …...;    103 × 10 =…...;   452 × 1000 =…...

358 × 10 = …...;   1977 × 100 =…...;    300 × 1000 =…...

b) 80 : 10 = …...;   400 : 100 =…...   ;6000 : 1000 =…...

300 : 10 = …...;     4000 : 100 =…...   ;60000 : 1000 =…...

2000 : 10 =…...;     40000 : 100 =…...   ;600000 : 1000 =…...

c) 64 × 10 =…...;    32 × 100 =…...;    95 × 1000 =…...

640 : 10 =…...;     3200 : 100 =…...;    95000 : 1000 =…...

Answer 1

a) 27 × 10 = 270;    72 × 100 = 7200;    14 × 1000 = 14000

86 × 10 = 860;     103 × 10 = 10300;    452 × 1000 = 452000

358 × 10 = 3580;     1977 × 100 = 197700;    300 × 1000 = 300000

b) 80 :10 = 8;     400 : 100 = 4    ;6000 : 1000 = 6

300 : 10 = 30;     4000 : 100 = 40    ; 60000 : 1000 = 60

2000 :10 = 200;     40000 :100 = 400    ;600000 : 1000 = 600

c) 64 × 10 = 640;    32 × 100 = 3200;    95 × 1000 = 95000

640 : 10 = 64;     3200 : 100 = 32;    95000 : 1000 = 95