Nhân với 10,100,1000...., Chia cho 10,100,1000....

Tính nhẩm:

a) 

\(\eqalign{ & 27 \times 10 = \ldots \cr & 86 \times 10 = \ldots \cr & 358 \times 10 = \ldots\cr} \)                \(\eqalign{ & 72 \times 10 = \ldots\cr & 103 \times 10 = \ldots\cr & 1977 \times 100 =\ldots \cr}\)               \(\eqalign{ & 14 \times 1000 = \ldots \cr & 452 \times 1000 = \ldots\cr & 300 \times 1000 = \ldots\cr}\)

b)

\(\eqalign{ & 80:10 = \ldots\cr & 300:10 = \ldots\cr & 2000:10 = \ldots\cr} \)               \(\eqalign{ & 400:100 = \ldots \cr & 4000:100 = \ldots \cr & 40000:100 = \ldots \cr}\)               \(\eqalign{ & 6000:1000 = \ldots \cr & 60000:1000 = \ldots \cr & 600000:1000 = \ldots \cr}\)

c)

\(\eqalign{ & 64 \times 10 = \ldots \cr & 640:10 = \ldots \cr}\)                  \(\eqalign{ & 32 \times 100 = \ldots \cr & 3200:100 = \ldots \cr}\)               \(\eqalign{ & 95 \times 1000 = \ldots \cr & 95000:1000 = \ldots \cr} \)

Tính:

\(\eqalign{a) & 63 \times 100:10 = \ldots \ldots \cr & \,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\, = \ldots \ldots \cr} \)

\(\eqalign{b) & 960 \times 1000:100 = \ldots \ldots \cr & \,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\, = \ldots \ldots \cr} \)

\(\eqalign{c) & 79 \times 100:10 = \ldots \ldots \cr & \,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\, = \ldots \ldots \cr} \)

\(\eqalign{d) & 90000:1000 \times 10 = \ldots \ldots \cr & \,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\, = \ldots \ldots \cr}\)

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