A = (6- 2 4/5).3 1/8 – 1 3/5:1/4 B = (-5/4 – -3/4 + 7/12) : 20% – 1/5

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