脱式计算.(能简算要简算的)①2×3.6+3.6×7+3.6②1.25×32×25③5.42-(3.75-0.58)④34.7-715+65.3-815⑤78×1115×117×1411⑥23×38+57÷83.-数学
题文
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答案
①2×3.6+3.6×7+3.6, =3.6×(2+7+1), =3.6×10, =36; ②1.25×32×25, =(1.25×8)×(25×4), =10×100, =1000; ③5.42-(3.75-0.58), =(5.42+0.58)-3.75, =6-3.75, =2.25; ④34.7-
=(34.7+65.3)-(
=100-1, =99; ⑤
=(
=1×1, =1; ⑥23× |