Odpowiedź:
1.
a)
1/2 + 3/4 = 2/4 + 3/4 = 5/4 = 1 1/4
1/3 + 7/9 = 3/9 + 7/9 = 10/9 = 1 1/9
5/6 + 1 1/4 = 10/12 + 1 3/12 = 1 13/12 = 2 1/12
b)
1 3/5 + 2 4/15 = 1 9/15 + 2 4/15 = 3 13/15
2 1/4 + 1 2/3 = 2 3/12 + 1 8/12 = 3 1/12
1 5/6 + 7/9 = 1 15/18 + 14/18 = 1 29/18 = 2 11/18
c)
7/10 + 4/5 + 1/2 = 7/10 + 8/10 + 5/10 = 15/10 + 5/10 = 20/10 = 2
3/4 + 5/7 + 1 1/2 = 3/4 + 1 2/4 + 5/7 = 1 5/4 + 5/7 = 2 1/4 + 5/7 = 2 7/28 + 20/28 = 2 27/28
7/8 + 1/2 + 2/4 = 7/8 + 1/2 + 1/2 = 7/8 + 1 = 1 7/8
d)
2 1/6 + 7/10 + 1 2/5 = 2 1/6 + 7/10 + 1 4/10 = 2 1/6 + 1 11/10 = 2 1/6 + 2 1/10 =
= 2 5/30 + 2 3/30 = 4 8/30 = 4 4/15
1 7/8 + 1/3 + 2 5/6 = 1 7/8 + 2/6 + 2 5/6 = 1 7/8 + 2 7/6 = 1 7/8 + 3 1/6 =
= 1 21/24 + 3 4/24 = 4 25/24 = 5 1/24
2 7/12 + 1 1/15 + 1/2 = 2 7/12 + 6/12 + 1 1/5 = 2 13/12 + 1 1/5 = 3 1/12 + 1 1/5 =
= 3 5/60 + 1 12/60 = 4 17/60
2.
a)
1/2 - 1/4 = 2/4 - 1/4 = 1/4
5/6 - 2/3 = 5/6 - 4/6 = 1/6
3/4 - 3/8 = 6/8 - 3/8 = 3/8
b)
3 5/9 - 1/6 = 3 10/18 - 3/18 = 3 7/18
1 3/4 - 5/6 = 1 9/12 - 10/12 = 21/12 - 10/12 = 11/12
2 1/9 - 1 5/6 = 2 2/18 - 1 15/18 = 1 20/18 - 1 15/18 = 5/18
c)
7/8 - 1/4 - 1/2 = 7/8 - 2/8 - 4/8 = 7/8 - 6/8 = 1/8
2 3/7 - 3/4 - 1 1/2 = 2 3/7 - 3/4 - 1 2/4 = 2 3/7 - 1 5/4 = 2 3/7 - 2 1/4 =
= 2 12/28 - 2 7/28 = 5/28
2 5/6 - 7/8 - 1 1/4 = 2 5/6 - 7/8 - 1 2/8 = 2 5/6 - 1 9/8 = 2 5/6 - 2 1/8 =
= 2 20/24 - 2 3/24 = 17/24
d)
3 11/12 - 5/9 - 1 3/4 = 3 11/12 - 1 9/12 - 5/9 = 2 2/12 - 5/9 = 2 1/6 - 5/9 =
= 2 3/18 - 10/18 = 1 21/18 - 10/18 = 1 11/18
10 - 3 1/4 - 1 3/5 = 6 3/4 - 1 3/5 = 6 15/20 - 1 12/20 = 5 3/20
7 - 2 1/2 - 1 4/5 = 4 1/2 - 1 4/5 = 4 5/10 - 1 8/10 = 3 15/10 - 1 8/10 = 2 7/10
Szczegółowe wyjaśnienie:
