a/2/3-7/6+3/4
=8/12-14/12+9/12
=-6/12+9/12
=3/12=1/3
b)(7 4/5)-(1 9/10)-5 4/5
39/5-19/10-29/5
=78/10-19/10-58/10
=59/10-58/10
=1/10
d)(-1/2)^3:(-1 3/8)- (-2)^3.75%
=(-1/2.-1/2.-1/2) - (-5/8) -(-8).0.75
=-1/8-(-5/8)-(-6)
=-3/4-(-6)
=-3/4- -24/4
=27/4
bài 2
a)-2/3+3/4x=5/6
3/4x=5/6- -2/3
3/4x=1/6
x=1/6:3/4
x=2/9
b)2/25 :(2x-1)= (-1/5)^2
2/25: (2x-1) = 1/25
2x-1=2/25:1/25
2x-1=2
2x=2+1
2x=3