a,\(\frac{3}{2}\cdot\frac{7}{3}+\frac{4}{3}\cdot\frac{1}{2}\)=\(\frac{7}{2}+\frac{2}{3}\)=\(\frac{25}{6}\)

b,\(\frac{2}{145}\cdot\left(\frac{1}{9}-\frac{13}{3}+1\right)\)=\(\frac{2}{145}.-\frac{29}{9}=-\frac{2}{45}\)

c.\(\frac{15}{7}:\left(-\frac{31}{12}-\frac{1}{18}-\frac{20}{9}\right)\)=\(\frac{15}{7}:\left(-\frac{175}{36}\right)=-\frac{108}{245}\)

\(1\frac{1}{2}.2\frac{1}{3}+1\frac{1}{3}.\frac{1}{2}\)

\(=\frac{3}{2}.\frac{7}{3}+\frac{4}{3}.\frac{1}{2}\)

\(=\frac{7}{2}+\frac{2}{3}\)

\(=\frac{25}{6}\)

\(\frac{1}{9}.\frac{2}{145}-4\frac{1}{3}.\frac{2}{145}+\frac{2}{145}\)

\(=\frac{2}{1305}-\frac{13}{3}.\frac{2}{145}+\frac{2}{145}\)

\(=\frac{2}{1305}-\frac{26}{435}+\frac{2}{145}\)

\(=\frac{-2}{45}\)

\(\left(-2\frac{7}{12}\right):2\frac{1}{7}-\frac{1}{18}:2\frac{1}{7}+2\frac{2}{9}:2\frac{1}{7}\)

\(=\frac{-17}{12}:\frac{15}{7}-\frac{1}{18}:\frac{15}{7}+\frac{20}{9}:\frac{15}{7}\)

\(=\left(\frac{-17}{2}-\frac{1}{18}+\frac{20}{9}\right):\frac{15}{7}\)

\(=\frac{-19}{3}.\frac{7}{15}\)

\(=\frac{-133}{45}\)

học tốt

a) \(\frac{3}{2}.\frac{7}{2}+\frac{5}{3}.\frac{1}{2}=\frac{21}{2}+\frac{5}{6}=\frac{63}{6}+\frac{5}{6}=\frac{68}{6}=\frac{34}{3}\)

b) \(\frac{1}{9}.\frac{2}{145}-\frac{13}{3}.\frac{2}{145}+\frac{2}{145}=\frac{2}{145}\left(\frac{1}{9}-\frac{39}{9}+\frac{9}{9}\right)=\frac{2}{145}\left(-29\right)=-0.4\)

c) \(\left(-\frac{91}{12}\right):\frac{15}{7}-\frac{1}{18}:\frac{15}{7}+\frac{20}{9}:\frac{15}{7}=\frac{7}{15}\left(-\frac{91}{12}-\frac{1}{18}+\frac{20}{9}\right)=\frac{7}{15}\left(-\frac{65}{12}\right)=-\frac{91}{36}\)

1/ -2020 + (1543 + 2020)

\(=-2020+1543+2020\)

\(=-2020+2020+1543\)

\(=0+1543\)

\(=1543\)
2/ (245 – 97) – 245

\(=245-97-245\)

\(=245-245-97\)

\(=0-97\)

\(=-97\)
3/ (-145) – (118 – 145)

\(=-145-118+145\)

\(=-145+145-118\)

\(=0-118\)

\(=-118\)
4/ (-36 + 89) - (145 + 89 – 36)

\(=-36+89-145-89+36\)

\(=\left(-36+36\right)+\left(89-89\right)-145\)

\(=0+0-145\)

\(=-145\)

học tốt

1/ -2020+(1543+2020)

=-2020+1543+2020

=(-2020+2020)+1543

=0+1543=1543

2/ (245-97)-245

=245-97-245

=(245-245)-97

=0-97=-97

3/ -145-118+145

=(-145+145)-118

=0-118=-118

4/ -36+89-145-89+36

=(-36+36)+(89-89)-145

=0+0-145=-145

mik đang cần gấp

giúp mik với ☹

1)-7264+(1543+7264)=-7264+1543+7264=1543

2)(144-97)-144=144-97-144=-97

3)(-145)-(18-145)=-145-18+145=-18

4)111+(-11+27)=111-11+27=100+27=127

5)(27+514)-(486-73)=27+514-486-73=541-486-73=55-73=-18

6)(36+79)+(145-79-36)=36+79+145-79-36=145

7)10-[12-(-9-1)]=10-[12+9+1]=10-12-9-1=-12

8)(38-29+43)-(43+38)=38-29+43-43-38=-29

9)271-[(-43)+271-(-17)]=271-[-43+271+17]=271+43-271-17=43-17=26

10)-144-[29-(+144)-(+144)]=-144-[29-144-144]=-144-29+144+144=-29+144=115

1) - 7264 + ( 1543 + 7264 )

= ( - 7264 + 7264 ) + 1543

= 0 + 1543

= 1543

2) ( 144 - 97 ) - 144

= ( 144 - 144 ) - 97

= 0 - 97

= - 97

3) ( - 145 ) - ( 18 - 145 )

= ( - 145 + 145 ) - 18

= 0 - 18

= - 18

4) 111 - ( - 11 + 107 )

= ( 111 + 11 ) + 107

= 122 + 107

= 229

5) ( 27 + 514 ) - ( 486 - 73 )

= ( 27 + 73 ) + ( 514 - 486 )

= 100 + 28

= 128

6) ( 36 + 79 ) + ( 145 - 79 - 36 )

= ( 36 - 36 ) + ( 79 - 79 ) + 145

= 0 + 0 + 145

= 145

1) - 7264 + ( 1543 + 7264 )

= ( - 7264 + 7264 ) + 1543

= 0 + 1543

= 1543

2) ( 144 - 97 ) - 144

= ( 144 - 144 ) - 97

= 0 - 97

= - 97

3) ( - 145 ) - ( 18 - 145 )

= ( - 145 + 145 ) - 18

= 0 - 18

= - 18

4) 111 - ( - 11 + 107 )

= ( 111 + 11 ) + 107

= 122 + 107

= 229

5) ( 27 + 514 ) - ( 486 - 73 )

= ( 27 + 73 ) + ( 514 - 486 )

= 100 + 28

= 128

6) ( 36 + 79 ) + ( 145 - 79 - 36 )

= ( 36 - 36 ) + ( 79 - 79 ) + 145

= 0 + 0 + 145

= 145

không biết 

= (1-2) + ( 3 -4 ) + ..... + ( 145 - 146 ) + 147

= -1 + -1 + .... + -1 + 147

rồi bn tự áp dụng công thức :

\(SSH=\left(\right)SC-SĐ\left(\right):KHOẢNGCÁCH+1\)

Tổng = ( SĐ + SC) X SSH : 2

1; - 7264 + (1543 + 7264)

= - 7264 + 1543 + 7264

= (-7264 + 7264) + 1543

= 0 + 1543

= 1543

2; (14497) - 144

= 14497 - 144

= 14353

3; (-145).(18145)

= -145.18145

= -2631025

4; 111 + (-11 + 27)

= 111 + 16

= 127

tham khảo

1/ -7264 + (1543 + 7264)

= -7264 + 7264 + 1543

= 0 + 1543 = 1543

2/ (144 - 97) - 144

= 144 - 144 - 97

= 0 - 97 = -97

3/ -145 - (18 - 145)

= -145 + 145 - 18

= 0 - 18 = 18

4/ 111 + (-11 + 27)

= 111 - 11 + 27

= 100 + 27 = 127

5/ (27 + 514) - (486 - 73)

= 27 + 514 - 486 + 73

= 27 + 73 + 514 - 486

= 100 + 28

= 28

6/ (36 + 79) + (145 - 79 - 36)

= 36 + 79 + 145 - 79 - 36

= 36 - 36 + 79 - 79 + 145

= 145

7/ 10 - [12 - (-9 - 1)]

= 10 - (12 + 9 + 1)

= 10 - (12 + 10)

= 10 - 10 - 12

= -12

8/ (38 - 29 + 43) - (43 + 38)

= 38 - 29 + 43 - 43 - 38

= 38 - 38 + 43 - 43 - 29

= -29

9/ 271 - [(-43) + 271 -(-17)]

= 271 - (-43 + 271 + 17)

= 271 + 43 - 271 - 17

= 43 - 17 = 26

10/ -144 - [29 - (+144) - (+144)]

= -144 - 29 + 144 + 144

= -29 + 144

= 115

5/ (27 + 514) - (486 - 73)

= 27 + 514 - 486 + 73

= 27 + 73 + 514 - 486

= 100 + 28

= 28

câu này là 128 nhé