900 x 0,5 =

(a)  

66 + 11 =

(a)  

50 x 30 =

(a)  

46 x 2 =

(a)  

84 x 100 =

(a)  

6 : 1000 =

(a)  

3/2 de 20 =

(a)  

2/5 de 50 =

(a)  

45 + 21 - 9 =

(a)  

(8 + 4) - 6 =

(a)  

7 x 5 + 6 : 2 =

(a)  

50% de 100 =

(a)