怎样算简便就怎样算.①8×0.4×12.5×25%②(27+15)×7×5③11998×1997+11998④197×9798+198.-数学
题文
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答案
①8×0.4×12.5×25%, =(8×12.5)×(0.4×25%), =100×0.1, =10; ②(
=(
=
=(
=2×5+1×7, =10+7, =17; ③
=
=
=1; ④197×
=197×(1-
=197×1-197×
=197-
=197-(
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题文
|
答案
①8×0.4×12.5×25%, =(8×12.5)×(0.4×25%), =100×0.1, =10; ②(
=(
=
=(
=2×5+1×7, =10+7, =17; ③
=
=
=1; ④197×
=197×(1-
=197×1-197×
=197-
=197-(
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