Вычислите. 1) (3- 3/4)+ 2 1/4. 2) (6- 2/10)-1 2/5. 3) (5/12+9/12)-1

Вычислите.
1) (3- 3/4)+ 2 1/4= 2 4/4- 3/4+ 2 1/4=
2 1/4+ 2 1/4= 4 2/4= 4 1/2
Или
(3- 3/4)+ 2 1/4= 3- 0,75+ 2,25=
2,25+ 2,25= 4,5

2) (6- 2/10)-1 2/5=
5 10/10- 2/10- 1 (2•2)/(5•2)=
5 8/10- 1 4/10= 4 4/10
Или
(6- 2/10) - 1 2/5= 6-0,2- 1,4=
5,8- 1,4= 4,4

3) (5/12+9/12)-1 =14/12- 1=
1 2/12- 1= 2/12= 1/6