Zadanie 1,strona 26,Szkoła podstawowa,klasa 4 (podręcznik)

Oblicz w pamięci

a) 8 x 7             b) 4 x 9 x 5             c) 7 x 7 x 2             d) 6 x 1 x 3 x 5

3 x 8                 7 x 5 x 2                 7 x 0 x 9                 8 x 4 x 1 x 1

9 x 6                 3 x 6 x 1                 5 x 4 x 8                 4 x 3 x 5 x 6

7 x 7                 8 x 0 x 3                 4 x 3 x 5                 5 x 4 x 2 x 8

 

Odpowiedz:

a) 8 x 7 = 56

3 x 8 = 24

9 x 6 = 54

7 x 7 = 49

b) 4 x 9 x 5 = (4 x 5) x 9 = 20 x 9 = 180

7 x 5 x 2 = 35 x 2 = 70

3 x 6 x 1 = 18

8 x 0 x 3 = 0

c) 7 x 7 x 2 = 49 x 2 = 98

7 x 0 x 9 = 0

5 x 4 x 8 = 20 x 8 = 160

4 x 3 x 5 =(4 x 5) x 3 = 60

d) 6 x 1 x 3 x 5 =(6 x 5) x 3 =30 x 3 = 90

8 x 4 x 1 x 1 = 32 x 1 = 32

4 x 3 x 5 x 6 = 12 x 5 x 6 = 12 x 30 = 360

5 x 4 x 2 x 8 = 20 x 2 x 8 = 40 x 8 = 32