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用简便方法计算下面各题.①284+378+122+216②125×5×7×8③82×99④44×27+27×55+27⑤960÷6÷16⑥1352-(352+365)⑦14.25+7.3+5.75+2.7⑧18.23-6.35-2.65⑨16.78-2.54+3.22-1.46

题目详情
用简便方法计算下面各题.
①284+378+122+216 ②125×5×7×8 ③82×99
④44×27+27×55+27 ⑤960÷6÷16 ⑥1352-(352+365)
⑦14.25+7.3+5.75+2.7            ⑧18.23-6.35-2.65 ⑨16.78-2.54+3.22-1.46         
⑩26.54-(5.23+6.54)
▼优质解答
答案和解析
①284+378+122+216
=(284+216)+(378+122)
=500+500
=1000;
②125×5×7×8
=(125×8)×(5×7)
=1000×35
=35000;
③82×99
=82×(100-1)
=82×100-82×1
=8200-82
=8118;
④44×27+27×55+27
=(44+55+1)×27
=100×27
=2700;
⑤960÷6÷16
=960÷(6×16)
=960÷96
=10;
⑥1352-(352+365)
=1352-352-365
=1000-365
=635;
⑦14.25+7.3+5.75+2.7
=(14.25+5.75)+(7.3+2.7)
=20+10
=30;
⑧18.23-6.35-2.65
=18.23-(6.35+2.65)
=18.23-9
=9.23;
⑨16.78-2.54+3.22-1.46
=(16.78+3.22)-(2.54+1.46)
=20-4
=16;
⑩26.54-(5.23+6.54)
=26.54-5.23-6.54
=26.54-6.54-5.23
=20-5.23
=14.77.