Сложение 11/20 + 6/15:
11/20 + 6/15 = 33/60 + 24/60 = 57/60 = 19/20
Вычитание:
а) 1/11 - 1/33:
1/11 - 1/33 = 3/33 - 1/33 = 2/33
в) 13/30 - 2/45:
13/30 - 2/45 = 29/90 - 4/90 = 25/90 = 5/18
д) 13/60 - 7/40:
13/60 - 7/40 = 13/60 - 21/120 = 13/60 - 21/120 = 13/60 - 21/120 = 23/120
б) 7/11 - 7/12:
7/11 - 7/12 = 24/44 - 77/44 = 17/44
г) 7/15 - 2/5:
7/15 - 2/5 = 7/15 - 6/15 = 1/15
е) 11/21 - 3/14:
11/21 - 3/14 = 22/42 - 9/42 = 13/42
Решение уравнения x + 2/9 = 5/6:
x + 2/9 = 5/6x = 5/6 - 2/9x = 15/18 - 4/18x = 11/18
Решение уравнения y - 3/28 = 12/35:
y - 3/28 = 12/35y = 12/35 + 3/28y = 336/980 + 105/980y = 441/980y = 63/140y = 9/20
Сложение 11/20 + 6/15:
11/20 + 6/15 = 33/60 + 24/60 = 57/60 = 19/20
Вычитание:
а) 1/11 - 1/33:
1/11 - 1/33 = 3/33 - 1/33 = 2/33
в) 13/30 - 2/45:
13/30 - 2/45 = 29/90 - 4/90 = 25/90 = 5/18
д) 13/60 - 7/40:
13/60 - 7/40 = 13/60 - 21/120 = 13/60 - 21/120 = 13/60 - 21/120 = 23/120
б) 7/11 - 7/12:
7/11 - 7/12 = 24/44 - 77/44 = 17/44
г) 7/15 - 2/5:
7/15 - 2/5 = 7/15 - 6/15 = 1/15
е) 11/21 - 3/14:
11/21 - 3/14 = 22/42 - 9/42 = 13/42
Решение уравнения x + 2/9 = 5/6:
x + 2/9 = 5/6
x = 5/6 - 2/9
x = 15/18 - 4/18
x = 11/18
Решение уравнения y - 3/28 = 12/35:
y - 3/28 = 12/35
y = 12/35 + 3/28
y = 336/980 + 105/980
y = 441/980
y = 63/140
y = 9/20