1)
~a) 54*113+45*113+113 = 113*(54+45+1)=113*100 = 11300
~b) (145*99+145)-(143*101-143) = 145(99+1)-143(101-1) = 145*100-143*100 = 100(145-143)=100*2 = 200
~c) 1+2-3+4-5+6-7+8-9+10 = 1-1-1-1-1+10 = 7

b) ( 145 * 99 + 145 ) - ( 143 * 101 - 143 )
= ( 145 * ( 99 + 1 ) ) - ( 143 * ( 101 - 1 )
= 145 * 100 - 143 * 100
= 14500 - 14300
= 200

c) 1 + 2 - 3 + 4 - 5 + 6 - 7 + 8 - 9 + 10
= 1 - 1 - 1 - 1  -1 + 10
= 7 

Bài 1:
a) 54.113 + 45.113 + 113 = 54.113 + 45.113 + 113.1
= 113.( 54 + 45 + 1 ) 
= 113.100 
= 11300
b) ( 145.99 + 145 ) - ( 143.101 - 143 ) = 145.( 99 + 1 ) - 143.( 101 - 1 )
= 145.100 - 143.100
= 14500 - 14300
= 200
c) 1 + 2 - 3 + 4 - 5 + 6 - 7 + 8 - 9 + 10 = 1 - 1 - 1 - 1  -1 + 10 = 7 

1) a) 54*113+45*113+113
=113*(54+45+1)
=113*100=11300
b) (145*99+145)-(143*101-143)
=145(99+1)-143(101-1)
=145*100-143*100
=100(145-143)
=100*2=200
c) 1+2-3+4-5+6-7+8-9+10
=1-1-1-1-1+10=7

Bài 2  nè bn .
A=11*40:5+12:4.
A=11*8+3
A=91

Cho mk 5 sao nha bn