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计算:1、(1)15+21+25+19(2)70+63+81+37+30+192、(1)17+19+234+21+183+26(2)(1+11+21+31)+(9+19+29+39)3、(1)35+121-35-21(2)152-19-13+19+223-324、(1)25-(25-14)-(14-7)(2)57-(50-28)+(44

题目详情
计算:
1、(1)15+21+25+19

(2)70+63+81+37+30+19
2、(1)17+19+234+21+183+26(2)(1+11+21+31)+(9+19+29+39)
3、(1)35+121-35-21             (2)152-19-13+19+223-32
4、(1)25-(25-14)-(14-7)(2)57-(50-28)+(44-28)-(57-26)
5、(1)199+99+9(2)9+98+397+247
6、(1)321-199(2)456-197-98
7、(1)2580-2547(2)1596-1296
   (3)365+97   (4)365-97
8、(1)150-85-15(2)1450-375-203-625
9、(1)38+83-55(2)(235+523+352)-(111+333+555)
10、(1)11-10+9-8+7-6+5-4+3-2+1(2)100+102-104+106-108+110-112+114-116+118.
▼优质解答
答案和解析
1(1)15+21+25+19
=(15+25)+(21+19)
=40+40
=80
(2)70+63+81+37+30+19
=(70+30)+(63+37)+(81+19)
=100+100+100
=300

2、(1)17+19+234+21+183+26
=(17+183)+(19+21)+(234+26)
=200+(40+260)
=200+300
=500
(2)(1+11+21+31)+(9+19+29+39)
=(1+9)+(11+19)+(21+29)+(31+39)
=10+30+50+70
=160

3、(1)35+121-35-21
=(35-35)+(121-21)
=100
(2)152-19-13+19+223-32
=(152-32)-(19-19)+(223-13)
=120+210
=330

4、(1)25-(25-14)-(14-7)
=25-25+14-14+7
=7
(2)57-(50-28)+(44-28)-(57-26)
=57-50+28+44-28-57+26   
=(57-57)+(28-28)+(44+26)-50
=70-50
=20

5、(1)199+99+9
=(200-1)+(100-1)+(10-1)
=310-3
=307
(2)9+98+397+247
=(10-1)+(100-2)+(400-3)+(250-3)
=760-9
=751

6、(1)321-199
=321-(200-1)
=321-200+1
=121+1
=122
(2)456-197-98
=456-(200-3)-(100-2)
=456-200-100+5
=156+5
=161

7、(1)2580-2547
=2500+80-(2500+47)
=2500-2500+(80-47)
=33
(2)1596-1296
=1500+96-(1200+96)
=(1500-1200)+(96-96)
=300
(3)365+97  
=365+(100-3)
=465-3
=462
(4)365-97
=365-(100-3)
=265+3
=268

8、(1)150-85-15
=150-(85+15)
=150-100
=50
(2)1450-375-203-625
=(1450-203)-(375+625)
=1247-1000
=247

9、(1)38+83-55
=121-55
=66
(2)(235+523+352)-(111+333+555)
=1110-999
=1110-(1000-1)
=1110-1000+1
=110+1
=111

10、(1)11-10+9-8+7-6+5-4+3-2+1
=(11-10)+(9-8)+(7-6)+(5-4)+(3-2)+1
=1+1+1+1+1+1
=6
(2)100+102-104+106-108+110-112+114-116+118
=(100+118)+(102-104)+(106-108)+(110-112)+(114-116)
=218-2-2-2-2
=218-8
=210