Đáp án:
A = (6- 2 4/5).3 1/8 - 1 3/5:1/4
A=(30-24/5).31/8-13/5.4
A=6/5.31/8-13/20
A=93/20-13/20
A=80/20=4
B= (-5/4 - -3/4 + 7/12) : 20% - 1/5
B=(-1/2+7/12):1/5-1/5
B=(-6/12+7/12) x 5 - 1/5
B=1/12 .5-1/5
B=5/12-12/60
B=25-12/60
B=13/60
Giải thích các bước giải:
A = (6- 2 4/5).3 1/8 - 1 3/5:1/4
A=(30-24/5).31/8-13/5.4
A=6/5.31/8-13/20
A=93/20-13/20
A=80/20=4
B= (-5/4 - -3/4 + 7/12) : 20% - 1/5
B=(-1/2+7/12):1/5-1/5
B=(-6/12+7/12) x 5 - 1/5
B=1/12 .5-1/5
B=5/12-12/60
B=25-12/60
B=13/60
