Odpowiedź:
zad. 3
5 cm = 5 razy 1/100 m = 5/100 m = 0,05 m
13 dag = 13 razy 1/100 kg = 13/100 kg = 0,13 kg
50 t = 50 razy 1000 kg = 50 000 kg
7 cm = 7 razy 10 mm = 70 mm
8 km = 8 razy 1000 m = 8000 m
zad.4
a) 3,2 + 5,64 = 8,84
5,43 + 12,7 = 18,13
17,2 + 3,51 + 2,1 = 22,81
b) 6,47 - 4,3 = 2,17
18,25 - 7,17 = 11,08
11,7 - 8,4 = 3,3
c) 11/13
3 i 9/7 = 4 i 2/7
15 i 8/5 = 16 i 3/5
d) 4/13
5 i 4/7
2 i 3/5 - 1 i 4/5 = 2 i 3/5 - 9/5 = 13/5 - 9/5 = 4/5
zad.5
a) 2 i 3/20 + 1/4 = 2 i 3/20 + 5/20 = 2 i 8/20 = 2 i 4/10 = 2,4
1 i 5/18 + 2 i 4/9 + 5/6 = 1 i 5/18 + 2 i 8/18 + 15/18 = 3 i 28/18 = 4 i 10/18 = 4 i 5/9
3 i 1/2 + 2 i 3/4 + 1 i 1/3 = 3 i 6/12 + 2 i 9/12 + 1 i 4/12 = 6 i 19/20
b) 2 i 1/20 - 3/4 = 2 i 1/20 - 15/20 = 41/20 - 15/20 = 26/20 = 1 i 6/20 = 1 i 3/10 = 1,3
1 i 7/18 - 2 i 2/9 = 1 i 7/18 - 2 i 4/18 = 1 i 3/18 = 1 i 1/6
2 i 1/7 - 5 i 2/3 = 2 i 3/21 - 5 i 14/21 = 45/21 - 119/21 = - 74/21 = - 3 i 11/21
Szczegółowe wyjaśnienie:
