能用简便算法用简便方法计算.
① 3 8×325+37.5%×475 = 3 8×(325+475) = 3 8×800 =300 ②64×( 3 4+ 1 16- 3 8) =64× 3 4+64× 1 16-64× 3 8 =48+4-24 =28 ③18.75× 5 8-7.75× 5 8-62.5% = 5 8×(18.75-7.75-1) = 5 8×10 =6.25 ④ 2 7÷ 8 3+ 4 7×37.5%+ 3 8÷7 = 2 7× 3 8+ 4 7× 3 8+ 3 8× 1 7 = 3 8×( 2 7+ 4 7+ 1 7) = 3 8×1 = 3 8
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