Odpowiedź:
11.
a)
2 7/11 + 3/22 = 2 14/22 + 3/22 = 2 17/22
b)
2 4/7 + 1 3/14 = 2 8/14 + 1 3/14 = 2 11/14
c)
7 7/15 + 2 2/9 = 7 21/45 + 2 10/45 = 9 31/45
d)
8 2/7 + 1 1/3 = 8 6/21 + 1 7/21 = 9 13/21
12.
a)
2 1/5 + 3 9/10 = 2 2/10 + 3 9/10 = 5 11/10 = 6 1/10
b)
1 8/9 + 5 4/7 = 1 56/63 + 5 36/63 = 6 92/63 = 7 29/63
c)
7 1/15 + 5 13/30 = 7 2/39 + 5 13/30 = 12 15/30 = 12 1/2
d)
7 5/6 + 2 2/9 = 7 30/36 + 2 8/36 = 9 38/36 = 10 2/36 = 10 1/18
13.
a)
15 5/8 + 1 6/7 = 15 35/56 + 1 48/56 = 16 83/56 = 17 27/56
b)
12 9/10 + 9 3/4 = 12 18/20 + 9 15/20 = 21 33/20 = 22 13/20
c)
14 7/12 + 2 7/16 = 14 28/48 + 2 21/48 = 16 49/48 = 17 1/48
d)
21 13/27 + 16 17/18 = 21 26/54 + 16 51/54 = 37 77/54 = 38 23/54
Szczegółowe wyjaśnienie:
