1.25×16=1.25×8+8
×
×
.(判斷對錯)
分析:將1.25×16變形為1.25×2×8,再計算求解,計算1.25×8+8,然后比較數(shù)值,即可判斷.
解答:解:1.25×16
=1.25×2×8
=2.5×8
=20
而1.25×8+8
=10+8
=18
所以,25×16=1.25×8+8是錯誤的;
故答案為:×.
點評:考查了小數(shù)乘法,注意靈活應(yīng)用運算律簡便計算.
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